Resin composition containing granular or powdery phenol-aldehyde resin

ABSTRACT

A resin composition comprising 
     (I) a granular or powdery resin which is a condensation product of a phenol, an aldehyde and optionally a nitrogen-containing compound having at least two active hydrogens and is characterized by (A) containing spherical primary particles and their secondary agglomerated particles each having a particle diameter of 0.1 to 150 microns, (B) having such a size that at least 50% by weight thereof can pass through a 100 Tyler mesh sieve, and (C) having a free phenol content, determined by liquid chromatography, of not more than 500 ppm, and 
     (II) at least one member selected from the group consisting of (1) a rubbery elastic material, (2) a thermoplastic resin and (3) a curable resin other than said granular or powdery resin (I) and/or a filler material other than said granular or powdery resin (I).

This is a continuation of application Ser. No. 452,737, filed Dec. 23,1982, now U.S. Pat. No. 4,476,277, issued Oct. 9, 1984.

This invention relates to a resin composition containing a novelgranular or powdery phenol-aldehyde resin, and more specifically, to aresin composition containing a novel granular or powdery phenol-aldehyderesin which has good storage stability and flow characteristics andreactivity and is suitable as a molding material.

Typical known phenol-aldehyde resins are novolak resins and resolresins.

The novolak resins are usually produced by reacting an excess of phenolwith formaldehyde in the presence of an acid catalyst such as oxalicacid (usually in an amount of 0.2 to 2%) while maintaining the moleratio of phenol to formaldehyde at, for example, 1:0.7-0.9. The novolakresins so produced have no self-crosslinkability and are thermoplasticbecause they are composed of, as main components, tri-, tetra- andpentamers resulting from the bonding of phenol moieties mainly bymethylene groups and contain almost no methylol groups. The novolakresins can be converted to cured resins by, for example, reacting themunder heat with a crosslinking agent, such as hexamine(hexamethylenetetramine), which is at once a formaldehyde generator andan organic base (catalyst) generator, or by mixing them with a solidacid catalyst and paraformaldehyde and reacting them under heat. Whensuch a novolak resin in accordance with the former method is used as amolding material, the resulting molded article will be foamed owing tothe generation of ammonia by the decomposition of hexamine, or theundecomposed part of hexamine or an organic base formed as a by-productwill remain in the molded article. This causes the defect that theproperties of the molded article are deteriorated, and the curingreaction is time-consuming. According to the latter curing method, thoseparts of the novolak resin which make contact with the paraformaldehydeand the acid catalyst undergo excessive crosslinking reaction, and it isdifficult to cure the resin uniformly. Furthermore, the acid catalyst orparaformaldehyde remains in the molded article to degrade its propertieswith the lapse of time, or troubles such as foaming occur owing to thedecomposition of the acid catalyst or paraformaldehyde during curing.Another defect is that since the novolak resin is obtained by thereaction of an excess of phenol and contains a relatively large amount(for example about 0.5 to about 2% by weight) of free phenol, a resincomposition containing it generates phenol when molded under heat andcauses troubles during the molding operation.

A process for producing cured novolak resin fibers was recentlysuggested which comprises heating a novolak resin at a high temperatureto form a product having a considerably high degree of condensation,purifying the product by removing components having a low degree ofcondensation thereby to obtain a product having a relatively high degreeof condensation and comprising phenol moieties linked to each other by 7to 10 methylene groups, melt-spinning the product to form novolakfibers, dipping the fibers in an aqueous solution of hydrochloric acidand formaldehyde and gradually heating the solution from roomtemperature to allow curing reaction to proceed from the surface of thefibers (Japanese Patent Publication No. 11284/1973). Granules or powdersobtained by cutting or pulverizing the cured fibers are expensive, anddo not possess good flow characteristics.

On the other hand, the known resol resins are produced usually byreacting phenol with an excess of formaldehyde in the presence of abasic catalyst (about 0.2 to 2% by weight based on the phenol) such assodium hydroxide, ammonia or an organic amine while maintaining the moleratio of phenol to formaldehyde at, for example, 1:1-2. The resol resinsso produced contain mono-, di- and trimers of phenol having a relativelylarge amount of methylol groups as main components and are veryreactive. It is the usual practice therefore to store them in arefrigerator as a water or methanol solution having a solidsconcentration of not more than 60%. The period for which such storage ispossible is about 3 to 4 months at the longest. To mold and cure such aresol resin, the water or methanol is removed and the resin is heated inthe optional presence of an acid catalyst. The rate of this curingreaction is very high, and, for example at 150° C., gellation occurswithin several tens of seconds. Since the resol resin has very highreactivity, it cannot be obtained as a stable granular or powdery solid.Furthermore, because a cured product of the resol resin has a highlydeveloped three-dimensional structure, it is very hard and itsconversion to a fine granular or powdery molding material is quitedifficult (Japanese Patent Publication No. 12958/1978). The resol resinsusually contain 1 to 10% by weight, based on the solids, of free phenol.

Several years ago, a process was disclosed which comprises reacting aphenol and formaldehyde in the presence of at least anitrogen-containing compound as a catalyst, and reacting the resultingcondensate with a hydrophilic polymeric compound to form a granular orpowdery resin (Japanese Patent Publication No. 42077/1978). Theresulting resin in the non-gelled state contains as much as about 5 to6% of free phenol (Examples 1 to 4 of the Japanese patent document), anda gelled product of the resin (Example 5 of the Japanese patentdocument) is a very hard non-reactive resin. Molded articles obtainedfrom the gelled resin have deteriorated properties because of itsinclusion of the nitrogen-containing compound used as catalyst or thehydrophilic polymeric compound.

A process is also known which comprises reacting a phenol andformaldehyde in a basic aqueous solution, mixing the resultingprepolymer with a protective colloid, and coagulating the prepolymerunder acidity to form inert solid beads (Japanese Patent Publication No.13491/1976). The coagulated product corresponds to a cured product of aresol resin, and has no reactivity. Furthermore, since it contains asalt or acid and the protective colloid, molded articles prepared fromit have degraded properties.

Attempts have been made to incorporate a phenol-formaldehyde resin inthermoplastic resins, rubbers or curable resins, but from the viewpointof its uses as a filler, it is first of all difficult to obtain it in ashape or form suitable as fillers. The phenol-formaldehyde resin alsohas the disadvantage that it contains substances which adversely affectthermoplastic resins, rubbers or curable resins.

The present inventors previously provided a novel granular or powderyphenol-aldehyde resin free from the aforesaid defects, and a process forits production.

It is an object of this invention to provide a resin compositioncontaining such a novel granular or powdery resin.

Another object of this invention is to provide a granular or powderyresin composition having good moldability which contains a granular orpowdery resin having good flow characteristics.

Still another object of this invention is to provide a resin compositionwhich contains a granular or powdery resin containing as small as notmore than 500 ppm of free phenol and is therefore safe and easy tohandle.

Yet another object of this invention is to provide a resin compositionwhich contains a granular or powdery resin capable of crosslinking withitself or with thermoplastic resins, rubbers or curable resins, and inwhich, therefore, the granular or powdery resin in the cured state canbe chemically combined with the thermoplastic resins, rubbers, etc. togive very uniform properties.

A further object of this invention is to provide a resin compositionwhich contains a granular or powdery nitrogen-containing resin and athermoplastic resin, and in the molded state, has excellent mechanicalproperties such as high strength, high hardness, low compression set andexcellent dimensional stability.

A still further object of this invention is to provide a resincomposition which contains a thermoplastic resin and gives moldedarticles having excellent electrical insulation or chemical resistanceand good platability.

A yet further object of this invention is to provide a resin compositioncontaining a rubbery elastic material, which contains a granular orpowdery resin having reactivity with the rubbery elastic material andtherefore in the cured state shows excellent mechanical properties suchas high strength, high hardness, low compression set, or excellentdimensional stability.

An additional object of this invention is to provide a resin compositionwhich contains a rubbery elastic material, and in the cured state, showsexcellent electrical insulation or heat resistance.

An additional object of this invention is to provide a resin compositionwhich contains a curable granular or powdery resin or a curable resin,is melted by heating, and in the cured state, has excellent wettabilitywith various fillers.

An additional object of this invention is to provide a resin compositionwhich contains a curable granular or powdery resin or a curable resin,and in the cured state, has excellent compression strength, chemicalresistance, electrical properties such as electric insulation, heatresistance or heat insulation, thus exhibiting the excellent propertiesof a phenol resin.

Other objects and advantages of this invention will become apparent fromthe following description and the accompanying drawings in which:

FIGS. 1 and 2 are each infrared absorption spectral charts by the KBrmethod of the granular or powdery resin obtained from phenol andformaldehyde obtained in Run No. 44 and from phenol, formaldehyde andurea obtained in Run No. 112, respectively.

In accordance with this invention, these objects and advantages of thisinvention are achieved by a resin composition comprising

(I) a granular or powdery resin which is a condensation product of aphenol, an aldehyde and optionally a nitrogen-containing compound havingat least two active hydrogens and is characterized by (A) containingspherical primary particles and their secondary agglomerated particleseach having a particle diameter of 0.1 to 150 microns, (B) having such asize that at least 50% by weight thereof can pass through a 100 Tylermesh sieve, and (C) having a free phenol content, determined by liquidchromatography, of not more than 500 ppm, and

(II) at least one member selected from the group consisting of (1) arubbery elastic material, (2) a thermoplastic resin and (3) a curableresin other than said granular or powdery resin (I) and/or a fillermaterial other than said granular or powdery resin (I).

The granular or powdery phenol-aldehyde resin used in this invention isproduced from a phenol, an aldehyde and optionally a nitrogen-containingcompound having at least two hydrogens by a method to be describedhereinbelow.

The granular or powdery phenol-aldehyde resin (to be referred to as thegranular or powdery resin) is characterized by (A), (B) and (C) statedabove. The limitation that the spherical primary particles and theirsecondary agglomerated particles have a particle diameter of 0.1 to 150microns (A), the limitation that at least 50% by weight of the entireresin can pass through a 100 Tyler mesh sieve (B), and the limitationthat the resin has a free phenol content, determined by liquidchromatography, of not more than 500 ppm (C) are based on the measuringmethods to be described hereinbelow.

A first feature of the product of the invention is that it consistsmostly of spherical primary particles and secondary particles resultingfrom the agglomeration of the primary particles, each having a particlediameter of 0.1 to 150 microns, preferably 0.1 to 100 microns asspecified in (A) above and is quite different from a forcibly pulverizedproduct of a cured product of a known novolak or resol resin or apulverization product of known cured novolak fibers.

Usually at least 30%, preferably at least 50%, of the granular orpowdery resin consists of spherical primary particles and theiragglomerated secondary particles each of which has a particle diameterof 0.1 to 150 microns, preferably 0.1 to 100 microns.

In the case of the granular or powdery resin containing thenitrogen-containing compound, usually at least 30%, preferably at least50%, thereof consists of spherical primary particles and secondaryparticles resulting from the agglomeration of the primary particles,each of which has a particle diameter of 0.1 to 100 microns, preferably0.1 to 50 microns. The expression 30% or 50% means that as defined inthe description of the method for measuring the particle diameter givenhereinbelow, it is 30% or 50% based on the number of entire particles(including the secondary agglomerated particles) of the resin in onevisual field of an optical microscope having a magnification of 100 to1,000. It is preferred that 70% to substantially 100% of the granular orpowdery product consists of spherical primary particles and secondaryagglomerated particles each having a particle diameter of 0.1 to 150microns (0.1 to 100 microns in the case of the resin containing thenitrogen-containing compound). Especially preferably, at least 30%,especially at least 50%, of the number (as an average of those in fivevisual fields) of particles in the visual field of a microphotograph inaccordance with the above definition consists of spherical primaryparticles and secondary agglomerated particles having a particlediameter in the range of 0.1 to 100 microns, preferably 0.1 to 50microns (in the case of the resin containing the nitrogen-containingcompound, 0.1 to 50 microns, preferably 0.1 to 20 microns).

Since the granular or powdery resin product used in this invention isformed mainly of the minute spherical primary particles and thesecondary agglomerated particles thereof, it is very small in size asspecified in (B) above. Thus, at least 50% by weight, preferably atleast 70% by weight, especially preferably at least 80% by weight, ofthe entire resin passes through a 100 Tyler mesh sieve (a 150 Tyler meshsieve in the case of the resin containing the nitrogen-containingcompound). The expression "passing through the sieve" does not excludethe exertion of a force which does not cause forcible destruction of theparticles (including the secondary agglomerated particles) in theprocedure of screening the granular or powdery product through thesieve, for example light crumpling of the granular or powdery product byhand, light pushing or levelling of the particles on the mesh by meansof a brush, or light tapping of the particles by hand because theparticles of the granular or powdery resin of this invention becomeagglomerated as their average particle size becomes smaller.

As specified in (C) above, the granular or powdery resin used in theinvention has a free phenol content, determined by liquidchromatography, of not more than 500 ppm. The preferred free phenolcontent is not more than 250 ppm, above all not more than 100 ppm, forthe resin containing the nitrogen-containing compound, and above 50 ppmbut not more than 400 ppm, especially above 50 ppm but not more than 300ppm. That the powdery or granular resin used in the invention has a verylow free phenol content is presumably because the process for itsproduction described hereinbelow comprises adding the phenol or thephenol and the nitrogen-containing compound or the diluted solutionthereof to the HCl-aldehyde bath to form a uniform solution at leastpartly, then forming very fine white suspended particles and developingthem into stable fine particles, and therefore, substantially all of thephenol added, especially the phenol which participates in the formationof the product of the invention, reacts with the aldehyde present inlarge excess. The granular or powdery products obtained by the methodsdisclosed in Japanese Patent Publication No. 42077/1978 cited above hasa free phenol content of as high as 0.3 to about 6% by weight. Incontrast, the free phenol content of the granular or powdery resin usedin the invention is quite small, and this fact is an important advantageof the process of the invention using granular or powdery resins of thiskind and is very surprising.

The granular or powdery resin used in this invention may also be definedby the ratio of the absorption intensity of an absorption peak assignedto the aromatic double bond to that of an absorption peak assigned tothe methylol group in its infrared absorption spectrum. The positions ofthe two peaks and their absorption intensities differ somewhat dependingupon the presence or absence of the nitrogen-containing compound.

The granular or powdery resin substantially free from thenitrogen-containing compound has a D₉₉₀₋₁₀₁₅ /D₁₆₀₀ ratio of from 0.2 to9.0 in its infrared absorption spectrum determined by a KBr tabletmethod, wherein D₁₆₀₀ represents the absorption intensity of anabsorption peak at 1600 cm⁻¹ (the peak assigned to benzene) andD₉₉₀₋₁₀₁₅ represents the highest absorption intensity of absorptionpeaks in the range of 990 to 1015 cm⁻¹ (the peaks assigned to themethylol groups). This resin further has a D₈₉₀ /D₁₆₀₀ ratio, whereinD₈₉₀ represents the absorption intensity of a peak at 890 cm⁻¹ (the peakassigned to a lone hydrogen atom on the benzene ring), of from 0.09 to1.0. Preferably, it has a D₉₉₀₋₁₀₁₅ /D₁₆₀₀ ratio of from 0.2 to 7.0,especially from 0.4 to 5.0, and a D₈₉₀ /D₁₆₀₀ ratio of from 0.1 to 0.9,especially from 0.12 to 0.8.

It is widely known with regard to phenol-formaldehyde resins that intheir infrared absorption spectra, the peak at 1600 cm⁻¹ shows anabsorption assigned to the benzene ring, the peaks at 990 to 1015 cm⁻¹show absorptions assigned to the methylol groups, and the peak at 890cm⁻¹ shows an absorption assigned to a lone hydrogen atom on the benzenering.

The granular or powdery resin containing the nitrogen-containingcompound has a D₉₆₀₋₁₀₂₀ /D₁₄₀₀₋₁₅₀₀ ratio of from 0.1 to 2.0 in itsinfrared absorption spectrum measured by a KBr tablet method, whereinD₁₄₅₀₋₁₅₀₀ represents the highest absorption intensity of absorptionpeaks in the range of 1450 to 1500 cm⁻¹ (the peaks assigned to thearomatic double bond) and D₉₆₀₋₁₀₂₀ represents the highest absorptionintensity of absorption peaks in the range of 960 to 1020 cm⁻¹ (thepeaks assigned to the methylol groups), and preferably further has aD₁₂₈₀₋₁₃₆₀ /D₁₄₅₀₋₁₅₀₀ ratio of 0.15 to 3.0 in the infrared absorptionspectrum, wherein D₁₂₈₀₋₁₃₆₀ represents the highest absorption intensityof absorption peaks in the range of 1280 to 1360 cm⁻¹ (the peaksassigned to the carbon-nitrogen bond).

Preferably, this resin has a D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.15 to0.6 and further a D₁₂₈₀₋₁₃₆₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.2 to 2.0.Especially preferably it has a D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.2to 0.4, and further a D₁₂₈₀₋₁₃₆₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.3 to 1.5.

The resin used in this invention further has such a characteristic inits infrared absorption spectrum determined by a KBr tablet method thatit has a D₁₅₈₀₋₁₆₅₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.3 to 4.5, preferablyfrom 0.75 to 2.0, especially preferably from 1.0 to 1.5, whereinD₁₅₈₀₋₁₆₅₀ represents the highest absorption intensity of absorptionpeaks in the range of 1580 to 1650 cm⁻¹.

Generally, it is difficult to determine the assignment of variousfunctional groups of a substance having a three-dimensional crosslinkedstructure by an infrared absorption spectroscopic method because peaksin its infrared absorption spectral chart frequently shift greatly. Butfrom the infrared absorption spectra of the phenol-aldehyde resin andvarious nitrogen-containing compounds, it has been determined that inthe infrared absorption spectrum of the resin of this invention, theabsorption peaks at 960 to 1020 cm⁻¹ are assigned to the methylolgroups, the absorption peaks at 1280 to 1360 cm⁻¹ are assigned to thecarbon-nitrogen bond, and the absorption peaks at 1450 to 1500 cm⁻¹ areassigned to the aromatic double bond.

The definite assignment of the absorptions at 1580 to 1650 cm⁻¹ isdifficult. But since the D₁₅₈₀₋₁₆₅₀ /D₁₄₅₀₋₁₅₀₀ using the highestabsorption intensity of the peaks at 1580 to 1650 cm⁻¹ can clearlydistinguish from the same ratio in a nitrogen-free phenol-formaldehyderesin, these absorptions can be recognized as characteristic absorptionsfor identifying the granular or powdery resin containing thenitrogen-containing compound.

It is understood that the ratio of absorption intensities in theinfrared absorption spectrum of the product of this invention, forexample, D₉₉₀₋₁₀₁₅ /D₁₆₀₀ =0.2-9.0 or D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ =0.1-2.0which is one parameter for specifying the granular or powdery resin usedin the invention, is a value associated with its structure and showsthat this resin contains a considerable amount of the methylol groupsand the methylol group content can be adjusted within a certain range.

The preferred product of this invention having a D₉₉₀₋₁₀₅₀ /D₁₆₀₀ ratioof from 0.2 to 7.0, or a D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.15 to0.6, and above all a D₉₉₀₋₁₀₁₅ /D₁₆₀₀ ratio of from 0.4 to 5.0 or aD₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.2 to 0.4 contain methylol groupsin a moderate degree of concentration and is stabler.

The fact that in its infrared absorption spectrum the granular orpowdery resin used in this invention has a D₈₉₀ /D₁₆₀₀ ratio of from0.09 to 1.0, preferably from 0.1 to 0.9, above all from 0.12 to 0.8,shows that in this resin, the reaction sites (the ortho- andpara-positions) of phenol molecules which participated in the reactionare moderately blocked by methylol groups.

Generally, one or both of the D₉₉₀₋₁₀₁₅ /D₁₆₀₀ ratio and the D₈₉₀ /D₁₆₀₀ratio of a cured product of a known resol resin are lower than those ofthe granular or powdery resin used in this invention. A cured product ofa known novolak resin cured with hexamine has a D₈₉₀ /D₁₅₀₀ ratio whichis generally lower than the lower limit of this ratio of the product ofthis invention.

It has been found by elemental analysis that the granular or powderyresin used in this invention which is substantially free from thenitrogen-containing compound is composed of carbon, hydrogen and oxygenand has the following composition.

C: 70 to 80% by weight

H: 5 to 7% by weight

O: 17 to 21% by weight

(Total 100% by weight)

It has also been found that many of the granular or powdery resins usedin this invention which contain the nitrogen-containing compound containat least 1% by weight, preferably 2 to 30% by weight of nitrogen.

The granular or powdery resin used in this invention can be obtainedeither as a resin whose curing reaction has not proceeded to a greatextent or as a resin whose curing reaction has proceeded to some extent,by the manufacturing process to be described hereinbelow. Accordingly,when the granular or powdery resin used in this invention is pressed at100° C. for 5 minutes in accordance with the heat fusibility test to bedescribed hereinbelow, at least a part of the resin fuses to form alumpy or plate-like mass (i), or the resin assumes the form of agranules or powder without substantial melting or melt-adhesion (ii).

Those granular or powdery resins used in this invention which haverelatively high heat fusibility as mentioned above shows a methanolsolubility, measured by the testing method to be given hereinbelow, ofat least 20% by weight, especially at least 30% by weight, and in somecases, at least 40% by weight.

Since the granular or powdery resin contains spherical primary particlesand their secondary agglomerated particles each having a particlediameter of 0.1 to 150 microns [the characteristic (A) describedhereinabove] in an amount of preferably at least 30%, and usually atleast 50% by weight, preferably at least 70% by weight, of the resinparticles can pass through a 100 Tyler mesh sieve, the resin has verygood flowability, and can be mixed with another material easily and in arelatively large amount. Furthermore, since many of the granular orpowdery resins used in this invention contain very minute sphericalprimary particles as a basic constituent, a cured molded articleprepared from a resin composition containing this resin has excellentmechanical properties, particularly high resistance to compression. Thegranular or powdery resins are very stable at ordinary temperatures andcontain considerable amounts of methylol groups. Hence, they showreactivity when heated, and give cured molded articles having not onlyexcellent physical and mechanical properties but also excellent thermalinsulation, heat resistance and electrical properties such as electricalinsulation, and chemical resistance.

Furthermore, the granular or powdery resin has a free phenol content ofusually not more than 500 ppm, and therefore, its handling is very easy,and safe. Further more, because of its very low free phenol content, aside-reaction attributed to the phenol is reduced in obtaining aprecursor article from the granular or powdery resin.

The granular or powdery resin does not substantially contain ahydrophilic polymeric compound because it is produced by a process inwhich the reaction system does not substantially contain a hydrophilicpolymeric compound.

The granular or powdery resin used in this invention is very fine andhas good storage stability and flow characteristics. Furthermore,because it contains a certain amount of methylol groups, it hasreactivity when molded into a precursor article and heated. Hence, itgives a cured article having uniform properties.

The granular or powdery resin used in this invention can be produced bycontacting a phenol, or both a phenol and a nitrogen-containing compoundcontaining at least two active hydrogens with a hydrochloricacid-aldehyde bath containing (a) hydrochloric acid (HCl) in aconcentration of 3 to 28% by weight, preferably 8 to 25% by weight,above all 12 to 22% by weight and (b) formaldehyde (HCHO) in aconcentration of 3 to 25% by weight, preferably 5 to 20% by weight,above all 7 to 15% by weight, and other aldehydes in a concentration of0 to 10% by weight with (c) the total concentration of hydrochloric acidand formaldehyde being 10 to 40% by weight, preferably 15 to 35% byweight, above all 20 to 32% by weight, while maintaining a bath ratio,defined by the quotient of the weight of the hydrochloric acid-aldehydebath divided by the total weight of the phenol and thenitrogen-containing compound, of at least 8.

Preferably, in addition to the three requirements (a), (b) and (c), thecomposition of the HCL-aldehyde bath is such that the mole ratio of thealdehyde in the bath to the phenol to be contacted with the bath or thephenol and the nitrogen-containing compounds combined is at least 2,especially at least 2.5, above all at least 3 [requirement (d)]. Thereis no particular upper limit to the above mole ratio (d). Preferably,the upper limit is 20, especially 15. The especially preferred moleratio (d) is from 4 to 15, above all from 8 to 10. The characteristicfeature of the aforesaid process is that a bath of an aqueous solutionof hydrochloric acid and formaldehyde having a considerably high HClconcentration and containing formaldehyde in molar excess to the phenolor both the phenol and the nitrogen-containing compound is contactedwith the phenol or both the phenol and the nitrogen-containing compoundat a bath ratio of at least 8, preferably at least 10.

Since the aforesaid process is carried out while the concentration ofeach of hydrochloric acid and aldehyde is kept at at least 3% by weight,and the bath ratio, at not less than 8, the weight percentage ofhydrochloric acid or aldehyde based on the weight of the phenol or thetotal weight of the phenol and the nitrogen-containing compound is atleast 24% by weight. Furthermore, since in this process, the totalconcentration of hydrochloric acid and formaldehyde is at least 10% byweight, the total weight of hydrochloric acid and aldehyde based on theweight of the phenol or the total weight of the phenol and thenitrogen-containing compound is at least 80% by weight. These reactionconditions are fundamentally different from the reaction conditions forthe production of known novolak and resol resins described hereinabove.

When the phenol or the phenol and the nitrogen-containing compound areto be contacted with the HCLaldehyde bath, the bath ratio (as definedhereinabove) is preferably at least 10, especially preferably 15 to 40.

In the aforesaid process, the phenol or the phenol and thenitrogen-containing compound are contacted with the HCl-formaldehydebath such that after contacting of the phenol with the bath, whitesuspended particles are formed and thereafter developed into a granularor powdery solid (preferably into a pink-colored granular or powderysolid when the nitrogen-containing compound is not used). The contactingof the phenol and the nitrogen-containing compound that the HCL-aldehydebath is conveniently carried out such that by adding the phenol and thenitrogen-containing compound together to the HCL-aldehyde bath or firstadding the nitrogen-containing compound and then the phenol to the bath,a clear solution is first formed and then white suspended particles areformed and thereafter developed into a granular or powdery solid. Incontacting the bath with the phenol or the phenol and thenitrogen-containing compound, it is preferred that before the whitesuspended particles are formed by the addition of the phenol, the bathbe stirred to form a clear, preferably uniform, solution of the phenolor the phenol and the nitrogen-containing compound, and that after theformation of the white suspended particles until the suspended particleschange to a solid, the bath (reaction mixture) be not subjected to amechanical shearing force such as stirring depending upon the ratio ofthe phenol to the nitrogen-containing compound or the reactionconditions.

The phenol may be added as such, but if desired, it may be diluted withformalin, an aqueous solution of hydrochloric acid, water, etc. prior tothe addition.

The temperature of the HCL-aldehyde bath with or without thenitrogen-containing compound dissolved therein, to which the phenol orboth the phenol and the nitrogen-containing compound (or the dilutedsolution thereof) are to be added is suitably not more than 90° C.,preferably not more than 70° C. If the temperature of the bath is higherthan 40° C., especially higher than 50° C., the rate of the reaction ofthe phenol or the nitrogen-containing compound with aldehyde increases,it is preferred to add the phenol or both the phenol and thenitrogen-containing compound as a solution diluted with formalin.Furthermore, since the rate of the reaction is high, it is preferred toadd the phenol, or both the phenol and the nitrogen-containing compound,preferably a diluted solution thereof as fine streams or smallestpossible droplets to the bath.

When the phenol or both the phenol and the nitrogen-containing compoundare added to the bath having a temperature of more than 40° C.,especially more than 50° C., the rate of the reaction of the phenol andthe nitrogen-containing compound becomes higher as the temperature ofthe bath becomes higher. Thus, within several minutes or instantaneouslyafter the contacting, white suspended particles form and are rapidlydeveloped into a granular or powdery solid.

A granular or powdery solid obtained by adding the phenol or both thephenol and the nitrogen-containing compound, either as such or as adiluted solution thereof, preferably a water diluted solution thereof,to the HCl-aldehyde bath maintained at not more than 40° C., preferably5° to 35° C., especially preferably 10° to 30° C., and after theformation of white suspended particles, completing the desired reactionat not more than about 50° C., preferably not more than 45° C. showsheat fusibility in the 100° C. fusibility test to be described belowbecause its curing reaction has not proceeded to a great extent.

On the other hand, a granular or powdery solid obtained by addingsubstantially all of the phenol or the phenol and thenitrogen-containing compound or the diluted solution thereof to theHCL-aldehyde bath maintained at not more than 45° C., preferably 15° to35° C. with stirring to form a clear solution, thereafter forming whitesuspended particles without stirring, then forming a granular or powderysolid with or without temperature elevation, and heating the solid at atemperature higher than 50° C., preferably 70° to 95° C., to completethe desired reaction has little or substantially no heat fusibility at100° C., or shows heat fusibility at a higher temperature, for exampleat 200° C., or has substantially no heat fusibility at such a hightemperature.

When both the phenol and the nitrogen-containing compound are used, itis possible in both of the abovedescribed cases to first add thenitrogen-containing compound to the HCl-formaldehyde bath and then addthe phenol alone.

Phenol is most preferred as the phenol. The phenol may also be a mixtureof at least 50% by weight, preferably at least 70% by weight, of phenolwith at least one known phenol derivative such as o-cresol, m-cresol,p-cresol, bisphenol A, bisphenol S, o-, m- or p-(C₂ -C₄ alkyl)-phenols,p-phenylphenol, xylenol, resorcinol and hydroquinone.

Suitable formaldehyde supply sources for the HCl-aldehyde bath includeformalin, trioxane, tetraoxane and paraformaldehyde.

The HCL-aldehyde bath used in this invention may include up to 10% byweight of an aldehyde other than formaldehyde in addition to theaforesaid formaldehyde supply sources. Examples of suitable otheraldehydes are monofunctional aliphatic aldehydes having 2 to 4 carbonatoms, glyoxal, furfural and benzaldehyde. Examples of themonofunctional aliphatic aldehydes include acetaldehyde,propionaldehyde, n-butyl aldehyde and iso-butyl aldehyde. Thesealdehydes may be used singly or as a mixture of two or more.

The nitrogen-containing compound used in this invention is a compoundcontaining at least two active hydrogens in the molecule. Preferably, itcontains in the molecule at least one group having active hydrogensselected from the class consisting of amino groups, amide groups,thioamide groups, ureylene groups and thioureylene groups. Examples ofsuch nitrogen-containing compound are urea, thiourea, methylolderivatives of urea or thiourea, aniline, melamine, guanidine,guanamine, dicyandiamide, fatty acid amides, polyamide, toluidine,cyanuric acid, and functional derivatives of these compounds. They maybe used either singly or as a mixture of two or more.

The granular or powdery resin solid formed in the bath as a result ofthe completion of the desired reaction is separated from theHCL-aldehyde bath, washed with water, preferably treated with an aqueousalkaline solution such as aqueous ammonia or a methanolic aqueousammonia solution to neutralize the adhering hydrochloric acid, and againwashed with water to give the desired product. As a matter of course, aresin having a relatively high solubility in methanol is preferablyneutralized with an aqueous alkaline solution.

The resin of this invention is characterized by containing the aforesaidfine granular or powdery phenolaldehyde resin.

The resin composition of this invention is described below according tovarious embodiments.

EMBODIMENT 1

The resin composition of this invention according to embodiment 1contains a thermoplastic resin in addition to the granular or powderyphenol-aldehyde resin described above.

A wide variety of thermoplastic resins known in the art of polymers canbe used in this invention. For example, there may be preferably usedversatile engineering plastics such as polyethylene resins,polypropylene resins, polystyrene resins, acrylic resins, vinyl resins,fluorine-containing resins, polyacetal resins, polyamide resins,polyester resins, polycarbonate resins, and polyurethan resins. Thepolyethylene resins, polypropylene resins, vinyl resins, polyamideresins and polyester resins are especially preferred. Thesethermoplastic resins may be used singly or as a mixture of two or more.

The aforesaid thermoplastic resins include both homopolymers andcopolymers, and the copolymers may be random, graft or block copolymers.The polyethylene resins contain preferably at least 50% by weight, morepreferably at least 85% by weight, of ethylene units in the polymerchain. The polypropylene resins contain preferably at least 50% byweight, more preferably at least 85% by weight, of propylene units inthe polymer chain. The polystyrene resins contain preferably at least50% by weight, more preferably at least 85% by weight, of styrene unitsin the polymer chain. The acrylic resins contain preferably at least 50%by weight, more preferably at least 85% by weight, of methyl or ethylacrylate or methacrylate units in the polymer chain.

The vinyl resins contain preferably at least 50% by weight, morepreferably at least 85% by weight, of units of a vinyl monomercontaining an ethylenically unsaturated bond such as vinyl chloride,vinylidene chlorice or vinyl acetate. Polyvinyl chlorice is especiallypreferred as the vinyl resin.

The fluorine-containing resins contain preferably at least 50% byweight, more preferably at least 85% by weight, of units of afluorine-containing vinyl monomer such as tetrafluoroethylene,fluoroethylene or hexafluoropropylene.

The polyethylene resins, polypropylene resins, poly-styrene resins,acrylic resins, vinyl resins and fluorine-containing resins may include,in addition to the aforesaid main units, other structural units whichare derived from such monomers as ethylene, propylene, acrylic acid,methacrylic acid, a lower alkyl (e.g., a methyl or ethyl) ester ofacrylic or methacrylic acid, styrene, α-methylstyrene, vinyl chloride,vinyl acetate and acrylonitrile.

Preferred polyacetal resins are, for example, polyoxymethylene andpoly(oxymethylene-oxyethylene)-copolymer. Thepoly(oxymethylene-oxyethylene)copolymer may contain not more than 15% byweight of oxyethylene units derived from ethylene oxide in the polymerchain.

Examples of preferred polyamide resins include polycaproamide (6-nylon),polyhexamethylene adipamide (6,6-nylon), polyhexamethylene sebacamide(6, 10-nylon), polyundecanamide (11-nylon), polydodecanamide (12-nylon),and polyundecamethylene terephthalamide (11,T-nylon).

The preferred polyester resins are unsaturated polyester resins, such aspolyethylene terephthalate, polytetramethylene terephthalate andpolyhexamethylene terephthalate.

Preferably, the polycarbonate resins are polycarbonates of bisphenols,particularly bisphenol A.

The thermoplastic resins used in this invention are well known in theart.

Strictly, the suitable mixing ratio between the granular or powderyresin and the thermoplastic resin in the resin composition in accordancewith embodiment 1 differs depending upon the properties of the granularor powdery resin used, for example whether it is heat-fusible or not, orupon the type of the thermoplastic resin used.

For example, the resin composition of this invention contains 1 part byweight of the thermoplastic resin and 0.01 to 20 parts by weight,preferably 0.02 to 3 parts, especially preferably 0.03 to 0.9 part, byweight, of the granular or powdery resin.

The resin composition of this invention is provided either as athermoplastic or thermosetting composition.

The present invention provides a particularly preferred resincomposition being thermoplastic and containing 1 part by weight of thethermoplastic resin and 0.05 to 0.5 part by weight of the granular orpowdery resin. A heat-setting thermosetting resin composition inaccordance with this invention is obtained generally when the granularor powdery resin has high reactivity and the amount of the thermoplasticresin is relatively small, or when the thermoplastic resin has highreactivity with the highly reactive granular or powdery resin althoughits amount is relatively large. Suitable proportions of the constituentresins which will give such a resin composition of this invention willbecome apparent from the following description.

As is seen from the foregoing description, the resin composition of thisinvention contains the powdery or granular or powdery phenol-aldehyderesin which when pressed at 100° C. for 5 minutes according to the heatfusibility test to be described hereinbelow, (i) is at least partlymelt-adhered to form a lumpy or plate-like product, or (ii) is in thegranular or powdery form with out substantial melting or melt-adhesion.It can be said that these species of the granular or powdery resin havethermosetting properties because they further undergo curing reactionupon reacting. The difference is that the resin having the property (i)is melted or melt-adhered upon heating because its curing reaction hasnot yet proceeded fully, whereas the resin having the property (ii)remains granular or powdery without melting or melt-adhesion uponheating because its curing reaction has further proceeded as comparedwith the resin having the property (i).

The resin composition of this invention comprises the thermoplasticresin as the other component. Since the resin composition of theinvention thus contains both the thermosetting resin and thethermoplastic resin, it generally has a greater tendency to bethermoplastic when the content of the thermosetting resin is low and tobe thermosetting when the content of the thermosetting granular orpowdery resin is large.

However, whether the resin composition of this invention isthermoplastic or thermosetting does not simply depend upon the mixingratio of the granular or powdery resin and the thermoplastic resin.

Investigations of the present inventors have shown that a resincomposition in accordance with this invention which is thermoplastic canbe advantageously provided by the following embodiments.

(1) When the heat-fusible species (i) described above is used as thegranular or powdery nitrogen-containing resin, it is advantageous to usethe granular or powdery resin in an amount of not more than 0.5 part byweight per part by weight of the thermoplastic resin.

(2) When the species (ii) which does not melt or melt-adhere is used asthe granular or powdery resin, the amount of the granular or powderyresin is advantageously not more than 2 parts by weight per part byweight of the thermoplastic resin.

(3) When a mixture of the species (i) and (ii) is used as the granularor powdery resin, it is preferred to adjust its amount such that perpart by weight of the thermoplastic resin, the amount of the resinspecies (i) is not more than 0.5 part by weight and the total amount ofthe mixture is not more than 1.5 parts by weight.

The resin compositions in accordance with this invention which arethermoplastic can be molded by methods generally used for the molding ofthermoplastic resins, such as extrusion molding or molding in a die. Theresulting molded articles have better mechanical properties such ashigher strength, higher hardness, lower compression set, betterdimensional stability and higher heat deformation temperatures, orbetter electric insulation, chemical resistance, platability or heatresistance than molded articles prepared from the thermoplastic resinused.

Investigations of the present inventors have also shown that a resincomposition in accordance with this invention which is thermosetting canbe advantageously provided by the following embodiments.

(1) When the species (i) is used as the granular or powdery resin, itsamount is preferably more than 0.5 part by weight, more preferably atleast 0.6 part by weight, per part by weight of the thermoplastic resin.

(2) When the species (ii) is used as the granular or powdery resin, itsproportion is preferably more than 2 parts by weight but does not exceed6 parts by weight, more preferably more than 2 parts by weight but doesnot exceed 3 parts by weight, per part by weight of the thermoplasticresin. As the thermoplastic resin, there can be used those thermoplasticresins which have reactivity with the granular or powdery resin, such aspolyamides, polyvinyl chloride and polyacetyl resins. If the granular orpowdery resin is used in amounts exceeding the aforesaid upper limits,it is difficult to obtain a molded article from the resulting resincomposition.

(3) When a mixture of the species (i) and (ii) is used as the granularor powdery resin, it is advantageous to adjust its amount such that perpart by weight of the thermoplastic resin, the total amount of themixture is more than 0.5 part by weight, but does not exceed 20 parts byweight, and the amount, x, of the resin species (i) and the amount, y,of the resin species (ii) satisfy the expression 6-0.3x>y>2-4x.

The resin compositions of this invention which are thermosetting can bemolded by methods generally used for the molding of thermosettingresins, for example by molding in a die. The resulting molded articleshave higher toughness, strength and hardness, lower compression set,better dimensional stability, electrical insulation, chemicalresistance, heat resistance and platability than those obtained from thegranular or powdery resin alone.

As required, the resin composition of this invention may contain variousfillers, for example fibrous materials such as glass fibers, carbonfibers or rock wool; granular or powdery materials such as carbon,silica, talc, alumina, silica-alumina, diatomaceous earth, calciumcarbonate, calcium silicate, magnesium oxide, clay, antimony oxide,hollow microspheres, or powders of metals such as iron, nickel andcopper; or organic materials such as wood flour, linter, pulp orpolyamide fibers. These fillers may be included in an amount of not morethan 30% by weight, preferably not more than 20% by weight, based on thetotal weight of the resin composition.

The resin composition of this invention which is thermoplastic can beproduced by introducing the granular or powdery phenol-aldehyde resin,the thermoplastic resin and optionally fillers into a melt extrudereither as such or after mixing them in the solid state in a mixer suchas a V-type blender, and melt-mixing them in the melt extruder. Theresin composition of this invention can be obtained there either aschips or pellets, or as a molded article.

It is also possible to feed a solid mixture of the aforesaid componentsof the resin composition of this invention which is thermoplastic or theaforesaid chips or pellets into a mold or an injection molding machine,and convert such a material into a molded article by molding in the moldor by injection molding.

The resin composition of this invention which is thermosetting may beconverted to a molded article usually by feeding a solid mixture of itscomponents in a mixer such as a V-type blender into a mold and moldingit there. If desired, it is also possible to first form chips or pelletsof the resin composition in a melt extruder adapted to rereduce the heathistory of the resin composition, and then to convert the resultingchips or pellets into the desired molded article. The operatingconditions for the mold usually include temperatures of 80° to 300° C.and periods of 0.1 to 10 hours and optionally pressures of 5 to 500kg/cm².

By utilizing the various excellent properties mentioned above, moldedarticles prepared from the resin compositions of this invention can besuitably used as electric and electronic component parts such as printedcircuit boards, switch boxes and circuit board for computers; castingmolds for thermoplastic resins; electrolytic cells; gears, bearings andtypes; heat insulating boards or structural materials for internalcombustion engines; interior and structural materials such as automotiveor aircraft dashboards; and sealing materials such as packing gasketsfor the opening and closing portions of refrigerators and tanks forchemicals.

EMBODIMENT 2

The resin composition of this invention in accordance with embodiment 2contains a rubbery elastic material in addition to the granular orpowdery resin.

The rubbery elastic material is a material which exhibits so-calledrubbery elasticity either as such or in the cured state. Such a rubberyelastic material is well known in the art, and includes, for example,natural rubber and synthetic rubbers such as polybutadiene,polyisoprene, copoly(butadiene-styrene),copoly(butadiene-acrylonitrile), copoly(ethylene-propylene),polyisobutylene, copoly(isobutylene-isoprene), polychloroprene,polyacrylate rubber, polysulfide, silicone rubbers, chlorinatedpolyethylene, fluorine rubber, chlorosulfonated polyethylene, andpolyurethan.

Conveniently, these rubbery elastic materials are used in the uncuredstate.

Among the above examples of the rubbery elastic materials,copoly(butadiene-acrylonitrile), polyacrylate rubber, fluorine rubber,copoly(butadiene-styrene), polychloroprene, chlorinated polyethylene,chlorosulfonated polyethylene, copoly(ethylene-propylene), and siliconerubbers are preferred in this invention.

The resin composition of this invention containing the rubbery elasticmaterial gives a cured product which has better heat resistance,abrasion resistance, adhesion, compression strength, hardness or tearstrength than a resin composition containing a conventionalphenolaldehyde resin.

In the resin composition of this invention, the granular or powderyresin has a better action of curing or thickening rubber than aconventional phenol-aldehyde resin.

The mixing ratio of the elastic material and the granular or powderyresin in the resin composition of this invention differs depending uponthe type of the elastic material or the properties of the resin, forexample, its methylol group content, or the end use of the composition.Generally, the granular or powdery resin is used in an amount of notmore than 2 parts by weight, preferably 0.03 to 2 parts by weight,especially preferably 0.05 to 1.5 part by weight, above all 0.1 to 1part by weight, per part by weight of the rubbery elastic material.

In addition to the rubbery elastic material and the granular or powderyresin, the resin composition of this invention may contain variousconventional additives for rubber compounds, such as vulcanizers,vulcanization aids, vulcanization accelerators, protective agents forrubber, processing agents for rubber, reinforcing agents, extenders andcoloring agents.

Examples of the vulcanizers include sulfur- or oxime-type vulcanizerssuch as sulfur, selenium, tellurium, sulfur chloride,p,p'-dibenzoylquinone dioxime and p-quinonedioxime; and organicperoxides such as 1,1-bis(t-butyl)-peroxy-3,3,5-trimethylcyclohexane,benzoyl peroxide, t-butylperoxyisopropyl carbonate, dicumyl peroxide,t-butylcumyl peroxide, methyl ethyl ketone peroxide, and cumylhydroperoxide.

Examples of the vulcanization aids includes zinc oxide, lead white,calcium hydroxide, litharge, stearic acid, oleic acid, lauric acid,linseed oil, cottonseed fatty acid, zinc stearate, lead oleate,dibenzylamine, diphenylguanidine phthalate, dibutyl ammonium oleate,diethanolamine and monoethanolamine.

Examples of the vulcanization accelerators include guanidines such asdiphenylguanidine, triphenylguanidine and diphenylguanidine phthalate;aldehyde and ammonia type accelerators such as hexamethylenetetramine,acetaldehyde and ammonia; amines or nitroso compounds such as anacetaldehyde/aniline mixture, an anhydrous formaldehyde/p-toluidinemixture, a butyraldehyde/ethylene polyamine mixture, or a condensationproduct of acrolein and an aromatic amine; thiazoles such as2-mercaptobenzothiazole, dibenzothiazyl disulfide andcyclohexylbenzothiazyl sulfenamide; thioureas such as thiocarbanilideand trialkylthioureas; thio-acid salts and dithio-acid salts such aszinc butylxanthate, zinc dimethyldithiocarbamate, zincisopropylxanthate, sodium diethyldithiocarbamate, palladiumdimethyldithiocarbamate, copper dimethyldithiocarbamate and leadpentamethylenedithiocarbamate; thiurams such as tetramethylthiurammonosulfide, tetramethylthiuram disulfide and dipentamethylenethiuramtetrasulfide; and mixtures of two or more of the above-exemplifiedvulcanization accelerators.

The vulcanizers, vulcanization aids or vulcanization accelerators mayeach be included in an amount of preferably 0.001 to 0.1 part by weightper part by weight of the rubbery elastic material in the resincomposition of this invention.

Examples of the protective agents for rubber include antioxidants suchas N-phenyl-1-naphthylamine, p-(p-tolyl-sulfonylamide)diphenylamine,phenylisopropyl p-phenylenediamine, and p-phenylphenol; antiozonantssuch as p-phenylene diamine,6-amino-2,2,4-trimethyl-2,2-dihydroqyinoline and nickeldibutyldithiocarbamate; crack inhibitors such asN-phenyl-2-naphthylamine and N,N'-diphenylethylenediamine; andinhibitors against the deleterious effects of copper, such asdi-β-naphthyl p-phenylenediamine and Calgon.

Examples of the processing agents for rubber include plasticizers orsoftening agents such as various esters, ketones, aromatic hydrocarbons,alcohols, mineral and vegetable oils, and coal tar products; binderssuch as phenolic resins, coumarone-indene resin and terpene styrene-typeresins; dispersing agents such as fatty acids, fatty acid soaps andamines; and combustion inhibitors such as trixylenyl phosphate andtricresyl phosphate.

Examples of the reinforcing agents include inorganic reinforcing agentssuch as carbon black, zinc oxide, clay, magnesium carbonate, variousgrades of silica, silicates, and calcium carbonate; and organicreinforcing agents such as asphaltic materials, phenolic resins, terpeneresins, coumarone-indene resin, various natural fibers, and varioussynthetic and semi-synthetic fibers.

Examples of the extenders are clay, talc, chalk, barite, lithopone,magnesium carbonate, zinc oxide and caldium carbonate.

Examples of the coloring agents include inorganic pigments such asvarious carbon blacks, titanium white, zinc oxide, red iron oxide, ironblue, cobalt blue, yellow ocher, chrome green and chrome orange; andorganic pigments such as phthalocyanine blue, Para Red, Hansa Yellow andorange lake.

The aforesaid rubber protecting agents, rubber processing agents,reinforcing agents, extenders or coloring agents are may be included inthe resin composition of this invention in an amount of up to 1 part byweight per part by weight of the rubbery elastic material.

The resin composition of this invention according to embodiment 2 may beprepared by melt-mixing the rubbery elastic material, the granular orpowdery resin and the various additives usually at a temperature of 70°to 150° C. using an open roll for example; or by mixing these materialtogether with a solvent suitable for the rubbery elastic material, suchas toluene, xylene, perchloroethylene, trichloroethylene, ketone, ether,alcohol, ethyl acetate, gasoline or light oil, and thereafter subjectingthe mixture to a solvent-removing treatment. During the melt mixing orthe solvent mixing and the solvent removing treatment, the curing of theresin composition of this invention proceeds, but such a resincomposition which has undergone curing reaction to some extent is alsoincluded within the resin composition of this invention.

Articles obtained by heat-treating the resin composition of thisinvention at a temperature of, for example, 100° to 200° C., such as oilseals, gaskets, packings, oil-resistant hoses, conveyor belts, rubberrolls, window frame rubbers, tires, diaphragms, electric componentparts, shoe soles and shoe heels, have excellent mechanical propertiessuch as excellent strength, high hardness, low compression set, andexcellent dimensional stability, or excellent electrical insulation orheat resistance, which are desirable for the respective articles.

EMBODIMENT 3

According to this embodiment, the resin composition of this invention isa curable resin composition comprising the granular or powderyphenol-aldehyde resin, and either another curable resin, or a fillermaterial or both.

Heat-curable or thermosetting resin is preferably used as the curableresin. Examples include resol resins, novolak resins, epoxy resins,furane resins, melamine resins, urea resins, and unsaturated polyesterresins. The resol, novolak, epoxy and furane resins are especiallypreferred. These curable resins may be used singly or as a mixture oftwo or more.

The filler material is included into the curable resin composition ofthis invention for various purposes. For example, for the purpose ofstrengthening a cured molded article prepared from it, or of impartingdimensional stability, heat resistance, fire retardancy, moldability orprocessability to the resin composition, filler materials which areusually used for such purposes can be used in this invention.

The filler material may be an inorganic or organic material, and may begranular or powdery or fibrous. Illustrative of such a filler materialare fibrous inorganic materials such as glass fibers, carbon fibers androck wool; carbon powder, silica, alumina, and silica-alumina; granularor powdery inorganic materials such as diatomaceous earth, calciumcarbonate, calcium silicate, magnesium oxide, clay, antimony oxide,hollow microspheres, or powders of metals such as iron, nickel orcopper; and organic materials such as wood flour, linter, pulp orpolyamide fibers.

The heat-curable resin composition of this invention comprises thegranular or powdery resin and one or both of the curable resin and thefiller.

Strictly, the suitable mixing ratio of these components in theheat-curable resin composition of this invention varies depending uponthe properties of the granular or powdery phenol-aldehyde resin used,for example whether it is heat-fusible or not, or upon the types of thecurable resin and the filler materials. The resin composition of thisinvention may contain the curable resin in an amount of 10 to 90% byweight, preferably 16 to 80% by weight, more preferably 24 to 70% byweight, based on the total amount of the curable resin and the granularor powdery phenol-aldehyde resin.

The heat-curable resin composition of this invention may generallycontain the filler material in an amount of 5 to 89% by weight,preferably 10 to 77% by weight, more preferably 15 to 63% by weight,based on the total amount of the filler and the granular or powderyphenol-aldehyde resin in the composition.

The heat-curable resin composition of this invention encompasses thefollowing three embodiments.

According to a first embodiment, the resin composition comprises all ofthe three components, i.e. the granular or powdery phenol-aldehyderesin, the curable resin and the filler. The granular or powderyphenol-formaldehyde resin contains reactive methylol groups.Accordingly, a cured product obtained from the resin composition isbelieved to have such a structure that the filler material is dispersedin a matrix composed of a cured intimate mixture of the granular orpowdery phenol-aldehyde resin and the curable resin. The powdery orgranular phenol-aldehyde resin may be the heat-fusible species (i), thesubstantially heat-infusible species (ii) or a mixture of (i) and (ii).It is believed that where the heat-fusible species (i) is a majorportion of the resin components, the particles of the granular orpowdery resin are bonded to each other during heat molding as a resultof melting and therefore are greatly disintegrated or form a continuousphase in the resulting cured article. On the other hand, it is believedthat where the granular or powdery resin constitutes a minor portion ofthe resin component, the individual particles of the granular or powderyresin, whether it is the species (i) or (ii), are cured and dispersedwithin the cured matrix in the cured article like independent islands,and act like a filler.

The heat curable resin composition in accordance with the firstembodiment comprises 10 to 85 parts by weight, preferably 20 to 75 partsby weight, above all 30 to 65 parts by weight, of the granular orpowdery resin, 10 to 85 parts by weight, preferably 15 to 70 parts byweight, above all 20 to 55 parts by weight, of the curable resin, and 5to 80 parts by weight, preferably 10 to 65 parts by weight, above all 15to 50 parts by weight, of the filler material, the total amount of thethree components being 100 parts by weight.

It is especially preferred in the first embodiment that the curableresin be a resol resin, a novolak resin or an epoxy resin, and the fiberbe glass fibers.

According to a second embodiment, the resin composition of thisinvention comprises the granular or powdery phenol-aldehyde resin andthe filler and is substantially free from the curable resin.

The granular or powdery resin may be the heat-fusible species (i) or amixture of the heat-fusible species (i) and the substantiallyheat-infusible species (ii). In the case of the mixture of the species(i) and (ii), it is preferred that the species (i) be used in a largeramount than the species (ii) and its amount be at least 25% by weightbased on the total weight of the granular or powdery resin and thefiller material.

The heat-fusible species (i) of the granular or powdery resin used inthis invention, even when molded singly under heat, can give a curedarticle having the inherent excellent properties such as excellentelectrical properties of the cured phenolic resin. As statedhereinabove, it is extremely difficult to prepare a cured molded articlefrom the resol resin alone, and the novolak resin can by itself give acured molded article but its quality is inferior. In view of this fact,the present invention has brought about an innovative advance in the artin that the granular or powdery resin used in this invention can byitself give a feasible cured article easily within very short periods oftime.

A cured article obtained from the resin composition in accordance withthe second embodiment is of very uniform quality because its matrix isderived only from the granular or powdery resin (not containing thecurable resin), and it has particularly excellent heat resistance andelectrical insulation.

The heat-curable resin composition of this invention comprises 20 to 95parts by weight, preferably 30 to 90 parts by weight, more preferably 40to 85 parts by weight, of the granular or powdery resin, and 5 to 80parts by weight, preferably 10 to 70 parts by weight, more preferably 15to 60 parts by weight, of the filler material, the total weight of thetwo components being 100 parts by weight.

Preferably, the filler material used in the second embodiment is glassfibers, hollow microspheres, pulp, carbon powder, calcium carbonate orpolyamide fibers.

According to a third embodiment, the resin composition of this inventioncomprises the granular or powdery phenol-aldehyde resin and the curableresin and is substantially free from the filler material. The granularor powdery phenol-aldehyde resin used in this embodiment may be theheat-fusible species (i), the substantially heat-infusible species (ii),or a mixture of the species (i) and (ii). The substantiallyheat-infusible species (ii) or a mixture of it with the species (i) ispreferred. The substantially heat-infusible species (ii) is used in anamount of 5 to 90% by weight, preferably 10 to 80% by weight, above all15 to 70% by weight, based on the total weight of the resin components.

The heat-curable resin composition according to the third embodimentcomprises 10 to 90 parts by weight, preferably 20 to 80 parts by weight,more preferably 30 to 70 parts by weight, of the granular or powderyresin, and 10 to 90 parts by weight, preferably 20 to 80 parts byweight, more preferably 30 to 70 parts by weight, of the curable resin.

In the third embodiment, the curable resin is preferably a resol resinor a novolak resin.

Unlike the novolak resin, the granular or powdery phenol-aldehyde resinused in the heat-curable resin composition of this invention has verycharacteristic reactivity such that it can be cured without using acrosslinking agent such as hexamine (in this sense, this resin may besaid to be self-curable). This characteristic reactivity is exhibited inthe production of a cured article from the heat-curable resincomposition of this invention. For example, the heat-fusible species ofthe granular or powdery resin reacts with the curable resin such as anovolak resin or a filler material such as polyamide fibers used at thetime of the curing reaction and can by itself cure without acrosslinking agent. Hence, a homogeneous cured article cured to a veryhard structure can be obtained.

When heated, the substantially heat-infusible species of the granular orpowdery resin itself further undergoes curing while substantiallymaintaining its particulate form, and at the same time reacts with theother curable resin at its interface. It, therefore, exhibits anexcellent action as a filler in the cured product, and a very hard curedarticle of uniform quality is obtained.

The heat-curable resin composition can be produced by mixing thegranular or powdery resin and the curable resin and/or the fillermaterial by using a V-blender, for example, if they are solidsubstances. When a solvent solution of a curable resin such as a resolresin or a furan resin is used, the resin composition may be prepared byfirst mixing these materials in a kneader, a mixer, a roll, etc., andthen removing the solvent.

The curable heat-curable resin composition of this invention may beconverted to a cured article by heat-treating it at a temperature of,for example, 80° to 250° C., for 0.1 to 10 hours, and as required underan elevated pressure of 1 to 500 kg/cm². Usually, the resin compositionis first molded and then heat-treated to obtain a cured product.

Cured articles obtained from the heat-curable resin compositions of thisinvention have better compression strength, chemical resistance,electrical properties such as electrical insulation, heat resistance orheat insulation than, for example, cured articles prepared from resincompositions containing conventional phenolic resins.

As required, the resin composition of this invention may contain knownadditives such as ultraviolet absorbers, heat stabilizers, coloringagents, plasticizers, curing agents, accelerators, lubricants andmodifers.

The following examples illustrate the present invention morespecifically.

The various properties given in the specification including thefollowing examples are measured or defined as follows:

The various abbreviations used in the examples are as follows:

TT: tetramethylthiuram disulfide

DM: dibenzothiazyl sulfide

M: 2-mercaptobenzothiazole

22: mixture of M+TT

ALTAX: benzothiazyl disulfide

Litharge: PbO (acid acceptor)

Light process oil: a kind of oil

DDM: dodecylmercaptan

GMF: accelerator containing p-dinitrosobenzene

TAIC: allyl isocyanurate

DOP: dioctyl phthalate

TET: tetraethyltetramine

1. Content of particles having a specified particle diameter:

A portion weighing about 0.1 g was sampled from five different sites ofone sample.

A part of each of the 0.1 g portions so sampled was placed on a slideglass for microscopic examination. The sample on the slide glass wasspread to minimize accumulation of particles for easy observation.

The microscopic observation was made with regard to that part of thesample in which about 10 to about 50 primary particles and/or thesecondary agglomerated particles thereof were present in the visualfiled of an optical microscope usually having a magnification of 100 to1,000. The sizes of all particles existing in the visual field of theoptical microscope were read by a measure set in the visual field of theoptical microscope and recorded.

The content (%) of particles having a size of, for example, 0.1 to 150μcan be calculated in accordance with the following equation. ##EQU1##N_(o) : the total number of particles whose sizes were read in thevisual field under the microscope, and

N₁ : the number of those particles in N_(o) which had a size of 0.1 to150μ.

For each sample, the average of values obtained from the five sampledportions was calculated.

2. Proportion of particles which passed through a Tyler mesh sieve:

About 10 g of a dried sample, if desired after lightly crumpled by hand,was accurately weighed. Over the course of 5 minutes, the sample was putlittle by little in a Tyler mesh sieve vibrator (the opening size of thesieve 200 mm in diameter; vibrating speed 200 rpm). After the end ofaddition, the sieve was vibrated further for 10 minuts. The proportionof the particles which passed through a 100 Tyler mesh sieve, forexample, was calculated from the following equation. ##EQU2## ω_(o) :the amount of the sample put in the sieve (g), ω₁ : the amount of thesample which remained on the 100 Tyler mesh sieve (g).

3. Free phenol content:

About 10 g of the sample which passed through the 100 Tyler mesh sievewas precisely weighed, and heat-treated under reflux for 30 minutes in190 g of 100% methanol. The hat-treated product was filtered through aNo. 3 glass filter. The filtrate was subjected to high-performanceliquid chromatography to determine the phenol content of the filtrate.The free phenol content of the sample was determined from a calibrationcurve separately prepared.

The operating conditions of high-performance liquid chromatography wereas follows:

Device: Model 6000 A made by Waters Co., U.S.A.

Column carrier: μ-Bondapak C₁₈

Column: 1/4 inch in diameter and 1 foot in length

Column temperature: room temperature

Eluent: methanol/water (3/7 by volume)

Flow rate: 0.5 ml/min.

Detector: UV (254 nm), range 0.01 (1 mV)

The phenol content of the filtrate was determined from a separatelyprepared calibration curve (showing the relation between the phenolcontent and the height of a peak based on phenol).

4. Infrared absorption spectrum and absorption intensities (seeaccompanying FIGS. 1 and 2):

The infrared absorption spectrum of a sample prepared by a usual KBrtablet method was measured by means of an infrared spectrophotometer(Model 225 made by Hitachi Limited).

The absorption intensity at a specified wavelength was determined in thefollowing way.

A base line is drawn tangent to a peak whose absorption intensity is tobe determined in the measured infrared absorption spectral chart. Letthe transmittance of the vertex of the peak be t_(p) and thetransmittance of the base line at the specified wavelength be t_(b),then the absorption intensity D at the specified wavelength is given bythe following equation. ##EQU3##

For example, the ratio of the absorption intensity of a peak at 890 cm⁻¹to that of a peak at 1600 cm⁻¹ is given by the ratio of the respectiveabsorption intensities determined by the above equation (i.e., D₈₉₀/D₁₆₀₀).

5. Heat fusibility at 100° C.:

About 5 g of a sample which passed through a 100 Tyler mesh sieve wasinterposed between two 0.2 mm-thick stainless steel sheets, and theassembly was pressed under an initial pressure of 50 kg for 5 minutes bymeans of a hot press kept at 100° C. (a single acting compressionmolding machine manufactured by Shinto Kinzoku Kogyosho Co., Ltd.). Thepress was released, and the hot-pressed sample was taken out frombetween the two stainless steel sheets, and observed. When the sample sotaken out was in the form of a flat plate as a result of melting ormelt-adhesion, it was judged that the sample had fusibility. When noappreciable difference was noted after the hot pressing, the sample wasdetermined to have infusibility.

6. Methanol solubility

About 10 g of a sample was precisely weighed (the precisely measuredweight is given by W_(o)), and heat-treated under reflux for 30 minutesin about 500 ml of 100% methanol. The mixture was filtered on a No. 3glass filter. The sample remaining on the filter was washed with about100 ml of methanol. Then, the sample remaining on the filter was driedat 70° C. for 2 hours. The weight of the dried sample was preciselyweighed (the precisely measured weight is given by W₁). The solubilityof the sample in methanol was calculated from the following equation.##EQU4##

7. Bulk density:

A sample was poured into a 100 ml measuring cylinder (whose brimcorresponded to a 150 ml indicator mark) from a height 2 cm above thebrim of the measuring cylinder. The bulk density of the sample isdefined by the following equation. ##EQU5## W: the weight in grams ofthe sample per 100 ml.

8. Weight increase by acetylation

About 10 g of a dry sample was precisely weighed, and added to about 300g of an acetylation bath consisting of 78% by weight of aceticanhydride, 20% by weight of acetic acid and 2% by weight oforthophosphoric acid. Then, the temperature was gradually raised fromroom temperature to 115° C. over the course of 45 minutes. The samplewas further maintained at 115° C. for 15 minutes. Then, the bath wasallowed to cool, and filtered on a No. 3 glass filter while being suckedby an aspirator carefully. The filtrate was fully washed with hot wateron the glass filter, and finally washed with a small amount of coldmethanol. Then, the residue on the glass filter was dried together withthe glass filter in a dessicator at 70° C. for 2 hours, and allowed tostand for a day and night in a dessicator containing silica gel as adrying agent. The dry weight of the residue on the filter was preciselyweighed.

The weight increase by acetylation, I, is given by the followingequation. ##EQU6## W_(o) : the precisely measured weight (g) of the drysample before acetylation,

W₁ : the precisely measure weight (g) of the dry sample afteracetylation.

9. Hydroxyl value:

Measured in accordance with the method of measuring the hydroxyl value(General Testing Method 377, Commentary on the Standards of CosmeticMaterials, first edition, published by Yakuji Nipposha, 1975).

10. Compression strength:

Measured in accordance with JIS K-6911-1979.

11. Heat distortion temperature:

Measured in accorddance with JIS K-6717.

12. Volume inherent restistivity (ohms-cm):

Measured according to the method described in JIS K-6911-1979.

13. Hardness and tensile strength and elongation:

Measured by the methods described in JIS K-6301-1975.

14. Compression set:

Measured in accordance with the method described in JIS K-6301-1975under the conditions: compression 25%, 70° C.×22 hours.

15. Flexural strength (kg/cm²) and compression strength (kg/cm²):

Measured in accordance with JIS K-6911-1979.

16. Heat resistant temperature:

A sample was heat-treated for 24 hours at various temperatures in adryer. The highest temperature during these heat-treatment operations atwhich no crack or gas blister was observed in the samples is defined asthe heat resistant temperature.

17. Heat conductivity (cal/cm sec °C.):

Measured in accordance with JIS A-1412-1968.

REFERENTIAL EXAMPLE 1

(1) In each run, a 2-liter separable flask was charged with 1,500 g of amixed aqueous solution at 28° C. of hydrochloric acid and formaldehydehaving each of the compositions shown in Table 1, and 62.5 g of anaqueous solution at 25° C. containing 80% by weight of phenol and 5% byweight of formaldehyde prepared from 98% by weight of phenol (theremaining 2% by weight being water), 37% formalin and water was added.The mixture was stirred for 20 seconds, and then left to stand for 60minutes. During the 60-minute standing, the contents of the flaskremained clear (Runs Nos. 1 and 20), or turned from a clear solution toa whitely turbid suspension (Runs Nos. 3, 9 and 18), or turned from aclear solution to a whitely turbid suspension which then turned palepink (Runs Nos. 2, 4 to 8, 10 to 17, and 19). Microscopic observationshowed that the pink-colored suspensions already contained sphericalparticles, agglomerated spherical particles, and a small amount of apowder. With occasional stirring, the contents of the separable flaskwere heated to 80° C. over the course of 60 minutes, and then maintainedat 80° to 82° C. for 15 minutes to obtain a reaction product. Thereaction product was washed with warm water at 40° to 45° C., treated ina mixed aqueous solution containing 0.5% by weight of ammonia and 50% byweight of methanol at 60° C. for 30 minutes, again washed with warmwater at 40° to 45° C., and then dried at 80° C. for 2 hours. Theproperties of the reaction products obtained by using the aqueoussolutions of hydrochloric acid and formaldehyde in various proportionsare shown in Table 2.

(2) For comparison, the following experiment was carried out. A 1-literseparable flask was charged with 282 g of distilled phenol, 369 g of 37%by weight formalin and 150 g of 26% by weight aqueous ammonia and withstirring, the mixture was heated from room temperature to 70° C. over 60minutes. Furthermore, the mixture was stirred at 70° to 72° C. for 90minutes, and then allowed to cool. While 300 g of methanol was addedlittle by little, the product was dehydrated by azeotropic distillationunder a reduced pressure of 40 mmHg. As a solvent, 700 g of methanol wasadded, and the product was withdrawn as a yellowish brown clear solutionof a resol resin.

When the solvent was removed from a part of the resulting resol resinunder reduced pressure, vigorous foaming occurred and the resin wasgelled. The gel was heat-cured under a nitrogen gas atmosphere at 160°C. for 60 minutes, and the resulting cured foam was pulverized to obtaina small amount of a powder which passed through a 100 Tyler mesh sieve.The heat-cured resol was very hard and extremely difficult to pulverizeinto a powder having a size of 100-mesh under even when various types ofpulverizers or ball mills or a vibratory mill for fluorescent X-rayswere used. The resulting heat-cured resol resin powder was treated witha mixed aqueous solution containing 0.5% by weight of ammonia and 50% byweight of methanol, washed with warm water, dehydrated and then driedunder the same conditions as described in section (1) above. Theproperties of the resulting product are shown in Table 2 as Run No. 21.

A 1-liter separable flask was charged with 390 g of phenol, 370 g of 37%by weight formalin, 1.5 g of oxalic acid and 390 g of water, and withstirring, the mixture was heated to 90° C. over 60 minutes and heatedwith stirring at 90° to 92° C. for 60 minutes. Then, 1.0 g of 35% byweight hydrochloric acid was added, and the mixture was further heatedwith stirring at 90° to 92° C. for 60 minutes. The product was cooled byadding 500 g of water, and then the water was removed by a siphon. Theresidue was heated under a reduced pressure of 30 mmHg, and heated underreduced pressure at 100° C. for 3 hours and then at 180° C. for 3 hours.On cooling, a novolak resin was obtained as a yellowish brown solidhaving a softening temperature of 78° to 80° C. and a free phenolcontent, measured by liquid chromatography, of 0.76% by weight. It has amethanol solubility of 100% by weight.

The resulting novolak resin was pulverized and mixed with 15% by weightof hexamethylenetetramine. The mixture was heat-cured in a nitrogen gasat 160° C. for 120 minutes, pulverized in a ball mill, and then passedthrough a 100 Tyler mesh sieve. The resulting powder was treated with amixed aqueous solution containing 0.5% by weight of ammonia and 50% byweight of methanol, washed with water, dehydrated and then dried underthe same conditions as described above. The properties of the resultingproduct are shown in Table 2 as Run No. 22.

The novolak resin was melt-spun at 136° to 138° C. through a spinnerethaving 120 orifices with a diameter of 0.25 mm. The as-spun filamentshaving an average size of 2.1 denier were dipped in a mixed aqueoussolution containing 1.8% by weight of hydrochloric acid and 18% byweight of formaldehyde at 20° to 21° C. for 60 minutes, heated to 97° C.over 5 hours, and then maintained at 97° to 98° C. for 10 hours. Theresulting cured novolak fibers were treated with a mixed aqueoussolution containing 0.5% by weight of ammonia and 50% by weight ofmethanol, washed with water, dehydrated and then dried under the sameconditions as described above. The product was pulverized in a ballmill, and passed through a 100 Tyler mesh sieve. The properties of theresulting product are shown in Table 2 as Run No. 23.

(3) Table 1 shows the concentrations of hydrochloric acid andformaldehyde used and the total concentration of hydrochloric acid andformaldehyde, and the mole ratio of formaldehyde to phenol. Table 2shows the contents of particles having a size of 1 to 50 microns, 1 to100 microns, and 1 to 150 microns, respectively, the proportion ofparticles which passed through a 100 Tyler mesh sieve, the D₉₉₀₋₁₀₁₅/D₁₆₀₀ and D₈₉₀ /D₁₆₀₀ ratios of the resulting products, and the weightincrease by acetylation of the products.

                  TABLE 1                                                         ______________________________________                                        Run   Concentration (wt. %)                                                                             Mole ratio of form-                                 No.   HCl    Formaldehyde Total aldehyde to phenol                            ______________________________________                                         1     3     1             4    1.1                                            2     3     25           28    23.8                                           3     5     5            10    4.9                                            4     5     10           15    9.6                                            5     5     22           27    20.9                                           6     7     30           37    28.5                                           7    10     6            16    5.8                                            8    10     20           30    19.1                                           9    12     3            15    2.8                                           10    15     5            20    4.9                                           11    15     25           40    23.8                                          12    18     10           28    9.6                                           13    20     7            27    16.8                                          14    22     4            26    4.0                                           15    22     17           39    16.2                                          16    25     6            31    5.8                                           17    25     25           50    23.8                                          18    28     3            31    2.8                                           19    28     7            35    6.8                                           20    33     1            34    1.1                                           21    Heat cured resol resin                                                  22    Hexamine heat-cured novolak resin                                       23    Cured novolak fibers                                                    ______________________________________                                    

                                      TABLE 2                                     __________________________________________________________________________                      Proportion of                                                  Content (%) of particles                                                                     particles hav-            Weight increase                   Run                                                                              having the following sizes                                                                   ing a size of                                                                             IR intensity ratio                                                                          by acetylation                    No.                                                                              1-50 μ                                                                          1-100 μ                                                                         1-150 μ                                                                         100 mesh under (wt. %)                                                                    D.sub.990-1015 /D.sub.1600                                                            D.sub.890 /D.sub.1600                                                               (wt. %)                           __________________________________________________________________________     1  1    1    1    1          0.35    0.10   8.6                                 (76) (100)                                                                              (100)                                                                              (83)                                                         2  3    3    3    4          0.45    0.11  19.5                                 (73) (100)                                                                              (100)                                                                              (79)                                                         3 13   13    13   8          0.42    0.11  21.7                                 (87) (100)                                                                              (100)                                                                              (75)                                                         4 50   89    96  62          0.86    0.18  25.4                               5 53   97   100  63          4.82    0.73  27.8                               6 12   12    12  18          6.68    1.02   30.06                               (76) (100)                                                                              (100)                                                                              (84)                                                         7 61   98   100  63          0.23    0.10  25.7                               8 83   100  100  78          2.36    0.58  33.5                               9 61   92   100  61          0.21    0.14  26.3                              10 83   100  100  76          0.25    0.11  28.1                              11 63   81   100  61          4.83    0.46  30.5                              12 99   100  100  98          1.52    0.40  32.8                              13 99   100  100  91          0.83    0.25  31.4                              14 69   94   100  69          0.26    0.17  24.7                              15 54   75    92  71          2.16    0.64  29.9                              16 84   98   100  79          0.37    0.12  28.5                              17 10   10    10   2          4.26    0.13  41.3                                 (86) (94) (100)                                                                              (73)                                                        18 50   87    96  62          0.27    0.10  23.8                              19 59   93   100  69          0.44    0.10  27.6                              20  2    2    2    1          0.23    0.10  19.7                                 (52) (95) (100)                                                                              (61)                                                        21 17   --   --   --          0.12    0.09   9.9                              22 58   --   --   --          5.47    0.07  18.7                              23 39   --   --   --          0.87    0.23  22.6                              __________________________________________________________________________

In Runs Nos. 1, 2, 3, 6, 17 abd 20 shown in Table 1, a large amount of asticky resin or a hard and large lumpy or plate-like mass formed at thebottom of the separable flask. In Runs Nos. 1, 2 and 20, only less than49 g of a solid was obtained from 50 g of phenol used.

In Runs Nos. 1, 2, 3, 6, 17 and 20, the contents of particles having asize of 1 to 50 microns, 1 to 100 microns and 1 to 150 microns and theproportion of particles having a size of 100 mesh under shown in Table 2are based on the entire solid including the sticky resin, lumpy mass andplate-like mass. The contents of these particles and the proportion ofparticles having a size of 100 mesh under based only on the granular andpowdery product in these Runs are shown in the parentheses in Table 2.

REFERENTIAL EXAMPLE 2

Each of six 20-liter reaction vessels was charged with 10.2 to 11.7 kgof a mixed aqueous solution containing 20% by weight of hydrochloricacid and 11% by weight of formaldehyde so that the bath ratio was asshown in Table 3. With stirring at 23° C., a mixed aqueous solutioncontaining 90% by weight of phenol and 3.7% by weight of formaldehydewas added in an amount of 1.8 kg, 1.5 kg, 0.9 kg, 0.7 kg, 0.4 kg, and0.25 kg, respectively. The bath ratios were 7.3, 8.5, 13.5, 17.0, 28.9,and 45.6, respectively.

In all of these cases, continued stirring after addition of the mixedaqueous phenol solution resulted in the abrupt formation of whitesuspended particles in 40 to 120 seconds. The stirring was stopped assoon as the white suspended particles formed, and the suspension wasleft to stand for 3 hours. The temperature of the inside of the reactionsystem gradually rose, and the contents of the vessel gradually turnedpale pink. In all of these runs, the formation of a slurry-like orresin-like product was observed in 30 minutes after the formation of thewhite suspended particles. The reaction mixture was washed with waterwith stirring. With stirring, the contents of the flask were heated to75° C. over 2 hours, and then heated with stirring at 75° to 76° C. for30 minutes. With the reaction mixture obtained in a system having a bathratio of 7.3, a large amount of resin melt-adhered to the stirring rodand the stirring became very difficult. In all runs, the contents of thereaction vessel turned from pale pink to pink and further to red duringthe temperature elevation.

The contents of the flask were then washed with water, treated in amixed aqueous solution containing 0.1% by weight of ammonia and 55% byweight of methanol at 50° C. for 60 minutes, and washed with warm waterat 80° C. for 60 minutes. The resulting granular or powdery product orlumpy mass was crumpled lightly by hand, and dried at 100° C. for 2hours. After the drying, the product had a water content of less than0.2% by weight. The resulting products are designated as samples of RunsNos. 31, 32, 33, 34, 35 and 36 in the increasing order of the bathratio.

Table 3 summarizes the maximum temperature reached of the reactionsystem from the initiation of the reaction to 3 hours after theformation of the white suspended particles; the yield of the reactionproduct; the presence or absence of spherical primary particles bymicroscopic observation; the proportion and bulk density of particleshaving a size of 100 Tyler mesh under in the reaction product; the heatfusibility at 100° C. of the reaction product; the elemental analysisvalues of the product; and the OH value of the product.

                                      TABLE 3                                     __________________________________________________________________________          Maximum     Proportion                                                                          Bulk density                                                                         Presence or                                          temperature of the 100                                                                          of the absence of  Elemental                                reached of  mesh under                                                                          100 mesh                                                                             spherical                                                                           Heat- analysis                           Run                                                                              Bath                                                                             the reaction                                                                         Yield                                                                              particles                                                                           under  primary                                                                             fusibility                                                                          (wt. %)   OH                       No.                                                                              ratio                                                                            system (°C.)                                                                  (wt. %)                                                                            (wt. %)                                                                             particles                                                                            particles                                                                           at 100° C.                                                                   C  H O  N value                    __________________________________________________________________________    31  7.3                                                                             39.5   110  29    0.25   Little                                                                              Fused 74.5                                                                             5.7                                                                             19.0                                                                             0.6                                                                             330                      32  8.5                                                                             38.5   113  63    0.23   Much  Infusible                                                                           74.7                                                                             5.6                                                                             19.3                                                                             0.3                                                                             335                      33 13.5                                                                             37.0   115  78    0.21   Mostly                                                                              "     75.0                                                                             5.7                                                                             20.0                                                                             0.2                                                                             360                      34 17.0                                                                             36.5   118  91    0.20   "     "     75.1                                                                             5.7                                                                             19.1                                                                             0.1                                                                             373                      35 28.9                                                                             35.5   118  98    0.19   "     "     76.3                                                                             5.7                                                                             18.7                                                                             0.0                                                                             385                      36 45.6                                                                             35.0   117  97    0.19   "     "     75.7                                                                             5.7                                                                             18.3                                                                             0.0                                                                             377                       21                                                                              (Comparison;                                                                            --   --    0.67   None  "     78.7                                                                             5.7                                                                             14.7                                                                             0.7                                                                             235                         see Table 1)                                                               22 (Comparison;                                                                            --   --    0.50   "     Fused 78.1                                                                             6.0                                                                             13.7                                                                             2.3                                                                             --                          see Table 1)                                                               23 (Comparison;                                                                            --   --    0.50   "     Infusible                                                                           74.8                                                                             5.6                                                                             19.2                                                                             0.5                                                                             325                         see Table 1)                                                               __________________________________________________________________________

The OH value of the product obtained in Run No. 22 could not be measuredbecause it fluctuated greatly.

In Run No. 31, a plate-like product and a lumpy product formed in atotal amount of as large as about 70% based on the entire solid formedat the bottom of the flask, and only about 30% of the entire solidconsisted of a granular or powdery product. But about 95% of thegranular or powdery product passed through a 100 Tyler mesh sieve. Theindication "little" for Run No. 31 is because the proportion of thegranular or powdery product based on the entire solid was as small asabout 30%. Hence, the method of Run No. 31 is not recommendable, but theresulting granular or powdery product is included within the granular orpowdery resin used in this invention.

In Runs Nos. 31 to 36, almost all of the granular or powdery productconsisted of particles having a size of 1 to 100 microns.

REFERENTIAL EXAMPLE 3

One thousand grams of a mixed aqueous solution at 25° C. containing 18%by weight of hydrochloric acid and 9% by weight of formaldehyde was putinto each of six 1-liter separable flasks. The room temperature was 15°C. With stirring, 40 g of phenol diluted with 5 g of water was added ata time to the solution. In each run, the stirring was stopped in 50seconds after the addition of the diluted solution of phenol. In 62 to65 seconds after the stopping of the stirring, white suspended particlesabruptly formed to give a milk-white product. The milk-white productgradually turned pink. The temperature of the liquid gradually rose from25° C., reached a maximum temperature of 35° to 36° C. in 16 to 17minutes after the addition, and then dropped. The reaction mixture wasallowed to stand at room temperature for 0.5 hour (Run No. 41), 1 hour(Run No. 42), 2 hours (Run No. 43), 6 hours (Run No. 44), 24 hours (RunNo. 45), and 72 hours (Run No. 46), respectively, washed with water,treated in 1% by weight aqueous ammonia at 15° to 17° C. for 6 hours,washed with water, dehydrated, and finally dried at 40° C. for 6 hours.

Table 4 summarizes the proportion of particles which passed through a100 Tyler mesh sieve, the D₉₉₀₋₁₀₁₅ /D₁₆₀₀ ratio and D₈₉₀ /D₁₆₀₀ ratios,the methanol solubility and the free phenol content of the products.

The samples obtained in Runs Nos. 41 to 46 all fused in a heatfusibility test conducted at 100° C. for 5 minutes.

FIG. 1 shows an infrared absorption spectral chart of the granular orpowdery resin obtained in Run No. 44. FIG. 1 also illustrates the methodof determining t_(p) to t_(b) required for obtaining the absorptionintensity D. A base line is drawn across a certain peak, and t_(p) andt_(b) can be determined as illustrated at the wavelength of the peak.

                  TABLE 4                                                         ______________________________________                                        Proportion of                                                                 particles                                                                     which passed                         Free                                     through a 100                                                                              IR intensity ratio                                                                           Methanol phenol                                   Run  Tyler mesh D.sub.990-1015 /  solubility                                                                           content                              No.  sieve (wt. %)                                                                            D.sub.1600                                                                              D.sub.890 /D.sub.1600                                                                 (wt. %)                                                                              (ppm)                                ______________________________________                                        41   59         0.53      0.10    97     310                                  42   83         0.87      0.12    80     116                                  43   94         1.06      0.13    71     85                                   44   97         1.12      0.13    67     74                                   45   96         1.12      0.14    64     73                                   46   97         1.13      0.13    63     70                                   ______________________________________                                    

REFERENTIAL EXAMPLE 4

A 1000-liter reaction vessel equipped with a stirring rod was chargedwith 800 kg of a mixed aqueous solution at 18° C. containing 18.5% byweight of hydrochloric acid and 8.5% by weight of formaldehyde, andwhile the mixed aqueous solution was stirred, 36.4 kg of a 88% by weightaqueous solution of phenol at 20° C. was added. After the addition ofall of the aqueous phenol solution, the mixture was stirred for 60seconds. The stirring was then stopped, and the mixture was left tostand for 2 hours. In the reaction vessel, white suspended particlesformed abruptly in 85 seconds after the addition of all of the aqueousphenol solution. The white suspended particles gradually turned palepink, and the temperature of the suspension gradually rose to 34.5° C.and decreased. Thereafter, while the mixed aqueous solution in which thereaction product formed was stirred, a valve secured to the bottom ofthe reaction vessel was opened, and the contents were withdrawn andseparated into the reaction product and the mixed aqueous solution ofhydrochloric acid and formaldehyde by using a nonwoven fabric (Nomex, atradename for a product of E. I. du Pont de Nemours & Co.). The reactionproduct was washed with water, dehydrated, dipped for a day and night ina 0.5% by weight aqueous solution of ammonia at 18° C., again washedwith water, and dehydrated to give 44.6 kg of the reaction producthaving a water content of 15% by weight.

2.0 Kg of the reaction product so obtained was dried at 40° C. for 3hours to give 1.7 kg of a sample (Run No. 47).

Table 5 shows the contents of 0.1-50 micron particles and 0.1-100 micronparticles of the dried sample obtained, the proportion of the particleswhich passed through a 100 mesh Tyler mesh sieve, the D₉₉₀₋₁₀₁₅ /D₁₆₀₀and D₈₉₀ /D₁₆₀₀ ratios, and the methanol solubility of the product.

                                      TABLE 5                                     __________________________________________________________________________       Content                                                                              Content                                                                              Proportion of particles                                         of 0.1-50                                                                            of 0.1-100                                                                           which passed through a    Methanol                           Run                                                                              micron micron 100 Tyler mesh                                                                            IR intensity ratio                                                                          solubility                         No.                                                                              particles (%)                                                                        particles (%)                                                                        sieve (wt. %)                                                                             D.sub.990-1015 /D.sub.1600                                                            D.sub.890 /D.sub.1600                                                               (wt. %)                            __________________________________________________________________________    47 96     100    99          1.18    0.13  47                                 __________________________________________________________________________

EXAMPLE 1

One part by weight of chips of 6-nylon (1013B, a tradename for a productof Ube Industries, Ltd.) was mixed with the granular or powdery resinobtained in Run No. 35 in an amount of 0, 0.015, 0.025, 0.04, 0.07,0.15, 0.4 and 0.8 part by weight, respectively. The mixture was kneadedand extruded by an extruder (Type 3AGM, made by Sumitomo HeavyIndustries, Ltd.), and cooled to form guts. The guts were converted intochips. The eight kinds of chips obtained were each extruded into a moldkept at 80° C. at a cylinder temperature of 250° C. to obtain eightkinds of molded articles each having a width of 5 cm, a length of 20 cmand a thickness of 0.5 cm (Runs Nos. 51 to 58).

Table 6 shows the flow of the mixed resin and the dispersibility of thegranular or powdery resin during extrusion molding, and the heatdistortion temperature, compression strength and volume inherentresistivity before or after boiling in water of each of the moldedarticles.

                                      TABLE 6                                     __________________________________________________________________________                           Molded article                                         Amount (parts          Volume inherent  Heat                                  by weight) of                                                                            Processability                                                                            resistivity (ohm-cm)                                                                    Compression                                                                          distortion                            Run                                                                              the product of                                                                        Flow of     Before                                                                             After                                                                              strength                                                                             temperature                           No.                                                                              Run No. 35                                                                            the resin                                                                          Dispersibility                                                                       boiling                                                                            boiling                                                                            (kg/mm.sup.2)                                                                        (°C.)                          __________________________________________________________________________    51 0       Excellent                                                                          --     10.sup.12                                                                          10.sup.9                                                                            8.7    65                                   52 0.015   Excellent                                                                          Good   10.sup.13                                                                          10.sup.11                                                                          10.1    73                                   53 0.025   Excellent                                                                          Excellent                                                                            10.sup.13                                                                          10.sup.11                                                                          11.5    84                                   54 0.04    Excellent                                                                          Excellent                                                                            10.sup.13                                                                          10.sup.12                                                                          13.7    95                                   55 0.07    Excellent                                                                          Excellent                                                                            10.sup.14                                                                          10.sup.13                                                                          14.3   101                                   56 0.15    Excellent                                                                          Excellent                                                                            10.sup.14                                                                          10.sup.13                                                                          15.1   112                                   57 0.4     Excellent                                                                          Excellent                                                                            10.sup.14                                                                          10.sup.13                                                                          15.2   137                                   58 0.8     Good Excellent                                                                            10.sup.14                                                                          10.sup.13                                                                          14.5   154                                   __________________________________________________________________________

EXAMPLE 2

One part by weight of a powder of 12-nylon (3035J, a tradename for aproduct of Ube Industries, Ltd.) was mixed with 0.3 part by weight ofeach of the products of Runs. Nos. 12, 21, 22, and 23 and glass staples(10 microns in diameter and 2 mm in length). The resulting mixtures weremolded into five types of molded articles (Runs Nos. 61 to 65) inaccordance with the method described in Example 1.

Table 7 shows the moldability of each of the mixtures and thecompression strength and the volume inherent resistivity before or afterboiling in water of each of the molded articles.

                                      TABLE 7                                     __________________________________________________________________________                       Volume inherent                                            Run                resistivity (ohm-cm)                                                                        Compression                                  No.                                                                              Material mixed                                                                        Moldability                                                                           Before boiling                                                                       After boiling                                                                        strength (kg/mm.sup.2).                      __________________________________________________________________________    61 Product of                                                                            Very good                                                                             10.sup.14                                                                            .sup. 10.sup.13                                                                      14.7                                            Run No. 12                                                                 62 Product of                                                                            Non-uniformity                                                                        10.sup.13                                                                            .sup. 10.sup.10                                                                      7.3                                             Run No. 21                                                                            in dispersion                                                      63 Product of                                                                            Much gas                                                                              10.sup.12                                                                            10.sup.8                                                                             5.1                                             Run No. 22                                                                            generated                                                          64 Product of                                                                            Great non-                                                                            10.sup.13                                                                            10.sup.9                                                                             7.2                                             Run No. 23                                                                            uniformity                                                                    in dispersion                                                      65 Glass staples                                                                         Great non-                                                                            10.sup.13                                                                            10.sup.8                                                                             7.6                                                     uniformity                                                                    in dispersion                                                      __________________________________________________________________________

EXAMPLE 3

One part by weight of each of a polyester resin (BELLPET EFG-6, atradename for a product of Kanebo Synthetic Fibers Co., Ltd.), apolycarbonate resin (MAKROLON 3100, a tradename for a product of BayerAG), a polyethylene resin (Hizex 2000, a tradename for a product ofMitsui Petrochemical Industries, Ltd.), nylon -66 (Nylon 2020, atradename for a product of Ube Industries, Ltd.) and a vinyl chlorideresin (RYULON 7001, a tradename for a product of Tekkosha Co., Ltd.) wasmixed with 0.45 part by weight of the product of Run No. 44. The mixturewas melted at a temperature of 150° to 300° C., and then cooled and cut.One hundred grams of each of the resulting samples was divided into tenequal portions, and treated for 5 minutes under a pressure of 100 to 500kg/cm² in a mold heated in advance to 100° to 250° C. between hotpresses, to obtain ten molded articles (width 13 mm, thickness 5.2-6.8mm, length 100 mm) from each of the samples (Runs Nos. 71 to 75).

Table 8 shows the heat distortion temperature and combustibility (matchtest by contact with the flame of a match for 10 seconds) of each of themolded products as the average properties of the ten samples in eachRun. For comparison, molded articles were produced similarly from thevarious resins alone, and the results are also shown in Table 8 (RunsNos. 76 to 80).

                  TABLE 8                                                         ______________________________________                                                              Heat                                                                          deform-                                                                       ation                                                                         temper-                                                                       ature     Combustibility by                             Run No. Resin used    (°C.)                                                                            a match test                                  ______________________________________                                        Invention                                                                     71      Polyester resin                                                                             135       Self-extinguishing                            72      Polycarbonate resin                                                                         160       Flame retardant                               73      Polyethylene resin                                                                           95       Burning very slow                             74      Nylon-66 resin                                                                              145       Self-extinguishing                            75      Vinyl chloride                                                                              105       Flame-retardant,                                      resin                   carbonized                                    Comparison                                                                    76      Polyester resin                                                                              70       Burning slow                                  77      Polycarbonate resin                                                                         130       Self-extinguishing                            78      Polyethylene resin                                                                           55       Burning slow                                  79      Nylon-66 resin                                                                               70       Burning slow                                  80      Vinyl chloride                                                                               70       Self-extinguishing                                    resin                                                                 ______________________________________                                    

EXAMPLE 4

One part by weight of a powder of 12-nylon (3035J, a tradename for aproduct of Ube Industries, Ltd.) was mixed with 1, 3 or 10 parts byweight of the product of Run No. 47, and the mixture was treated under apressure of 300 kg/cm² for 20 minutes in a mold heated in advance to150° to 170° C. between hot presses to produce ten molded plates (width13 mm, thickness 0.5-0.6 mm, length 100 mm) in each of Runs Nos. 81 to83 as shown in Table 9. For comparison, ten molded plates were preparedfrom a powder of 12-nylon alone under the same conditions as aboveexcept that a mold heated to 150° C. was used (Run No. 84).

Table 9 shows the heat shrinkage residual ratio of each molded sheetupon standing for 30 minutes in a desiccator at 200° C. in the air, theheat fusibility of each plate when it was maintained in an atmosphere ofnitrogen gas at 500° C. for 10 minutes, and the volume inherentresistivity of each molded plate before and after boiling in water.

                  TABLE 9                                                         ______________________________________                                                                        Volume inherent                               Product of   Heat               resistivity                                   Run No. 47   shrinkage Heat     (ohm-cm)                                             (parts by residual  fusibil-                                                                             Before After                                Run No.                                                                              weight)   ratio (%) ity    boiling                                                                              boiling                              ______________________________________                                        Invention                                                                     81     1         95.4      Heat-  10.sup.14                                                                            10.sup.13                                                       infusible                                          82     3         98.6      Heat-  10.sup.14                                                                            10.sup.14                                                       infusible                                          83     10        99.5      Heat-  10.sup.14                                                                            10.sup.14                                                       infusible                                          Comparison                                                                    84     0         No shape  Fused  10.sup.9                                                                             10.sup.8                                              retention                                                    ______________________________________                                    

REFERENTIAL EXAMPLE 5

(1) A 2-liter separable flask was charged with 1.5 kg of a mixed aqueoussolution at 25° C. of hydrochloric acid and formaldehyde in the variousconcentrations shown in Table 10, and while the mixed aqueous solutionwas stirred, 125 g of a mixed aqueous solution at 25° C. containing 20%by weight of phenol, 20% by weight of urea and 14.6% by weight offormaldehyde prepared from 98% phenol (the remaining 2& by weight beingwater), urea, 37% by weight formalin and water was added. The mixturewas then stirred for 15 seconds, and thereafter left to stand for 60minutes. During the 60-minute standing, the contents of the separableflask remained clear (Runs Nos. 101 and 120 in Table 10), or turned froma clear solution to a whitely turbid suspension and remained whitelyturbid (Runs Nos. 103, 109 and 118 in Table 10), or turned from a clearsolution to a whitely turbid suspension and gave a white precipitate(Runs Nos. 102, 104-108, 110-117, and 119). By microscopic observation,this white precipitate was found to contain spherical particles, anagglomerated mass of spherical particles, and a small amount of apowder. Then, with occasional stirring, the contents of the separableflask were heated to 80° C. over 60 minutes and then maintained at 80°to 82° C. for 15 minutes to obtain a reaction product. The reactionproduct was washed with warm water at 40° to 45° C., treated at 60° C.for 30 minutes in a mixed aqueous solution containing 0.5% by weight ofammonia and 50% by weight of methanol, again washed with warm water at40° to 45° C., and then dried at 80° C. for 2 hours. The properties ofthe reaction products are shown in Table 11.

(2) Table 10 summarizes the concentrations of hydrochloric acid andformaldehyde used, the total concentration of hydrochloric acid andformaldehyde, the proportion of the weight of the HCl-formaldehydesolution based on the total weight of the phenol and urea, and the moleratio of formaldehyde to phenol+urea. Table 11 summarizes the contentsof particles having a size of 0.1 to 50 microns and 0.1 to 100 micronsrespectively, the amount of particles which passed through a 150 Tylemesh sieve, and the D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀, D₁₂₈₀₋₁₃₆₀ /D₁₄₅₀₋₁₅₀₀ andD₁₅₈₀₋₁₆₅₀ /D₁₄₅₀₋₁₅₀₀ ratios of the resulting products.

                                      TABLE 10                                    __________________________________________________________________________                      Proportion of the weight of                                                   the HCl-HCHO bath based on the                              Concentrations of the                                                                           total amount of phenol and                                                                     Mole ratio of total                        HCl-formaldehyde (wt. %)                                                                        urea (wt. %)     HCHO to the mixture                        Run No.                                                                            HCl HCHO                                                                              Total                                                                              HCl     HCHO     of phenol and urea                         __________________________________________________________________________    101   3  1    4    90      30      1.6                                        102   3  28  31    90     840      21.2                                       103   5  2    7   150      60      2.3                                        104   5  10  15   150     310      8.1                                        105   5  22  27   150     660      16.8                                       106   7  30  37   210     900      22.6                                       107  10  7   17   300     210      5.9                                        108  10  18  28   300     540      13.9                                       109  12  3   15   360      90      3.0                                        110  15  5   20   450     150      4.5                                        111  15  22  37   450     660      16.8                                       112  18  10  28   540     300      8.1                                        113  20  7   27   600     210      5.9                                        114  22  4   26   660     120      3.8                                        115  22  17  39   660     510      13.2                                       116  25  6   31   750     180      5.2                                        117  25  25  50   750     750      19.0                                       118  28  3   31   780     790      2.6                                        119  28  7   35   780     210      5.9                                        120  33  1   35   990      30      1.6                                         21  Heat-cured product of resol                                               22  Hexamine heat-cured product of novolak                                    23  Cured novolak fibers                                                     __________________________________________________________________________

                                      TABLE 11                                    __________________________________________________________________________                       Proportion                                                 Content of  Content of                                                                           of particles                                               particles   particles                                                                            which passed                                               with a size with a size                                                                          through a 150                                                                        IR intensity ratio                                       of 0.1-50                                                                            of 0.1-100                                                                           Tyler mesh                                                                           D.sub.1580-1650 /                                                                   D.sub.1280-1360 /                                                                   D.sub.960-1020 /                        Run No.                                                                            microns (%)                                                                          microns (%)                                                                          sieve (wt. %)                                                                        D.sub.1450-1500                                                                     D.sub.1450-1500                                                                     D.sub.1450-1500                         __________________________________________________________________________    101  13 (86)                                                                              13 (100)                                                                             13 (87)                                                                              0.31  0.29  0.10                                    102  6  (45)                                                                              6  (58)                                                                              6  (52)                                                                              0.46  0.53  0.53                                    103  32 (91)                                                                              32 (98)                                                                              32 (93)                                                                              0.73  0.46  0.14                                    104  56     78     65     1.67  0.73  0.45                                    105  38     47     58     1.41  0.86  0.47                                    106  7  (18)                                                                              7  (39)                                                                              7  (66)                                                                              1.36  0.75  0.48                                    107  99     99     93     1.34  0.88  0.31                                    108  90     99     88     1.26  0.97  0.38                                    109  78     85     72     1.18  0.65  0.29                                    110  92     100    87     1.29  0.96  0.23                                    111  43     87     68     1.16  0.85  0.37                                    112  100    100    100    1.37  1.10  0.29                                    113  100    100    100    1.26  1.08  0.26                                    114  72     77     66     1.38  0.54  0.19                                    115  50     76     76     1.54  0.97  0.56                                    116  84     96     81     1.49  0.66  0.31                                    117  10 (63)                                                                              10 (68)                                                                              10 (73)                                                                              1.01  0.78  0.64                                    118  38     69     65     1.34  0.47  0.19                                    119  46     75     69     1.14  0.77  0.32                                    120  7  (18)                                                                              7  (49)                                                                              7  (64)                                                                              0.75  0.39  0.12                                     21  17     --     --     0.22  0.10  0.03                                     22  58     --     --     0.50  0.13  3.73                                     23  39     --     --     0.15  0.08  0.14                                    __________________________________________________________________________

In Runs. Nos. 101, 102, 106, 117 and 120 in Table 10, a large amount ofa sticky resin, a hard large lumpy or plate-like mass formed at thebottom of the separable flasks.

In Runs Nos. 101, 102 and 120, only less than 49 g of a solid wasobtained from 25 g of phenol and 25 g of urea used.

The contents of particles having a size of 0.1-50 microns and 0.1-100microns and the proportion of particles which passed the 150 Tyler meshsieve given in Table 11 for Runs Nos. 101, 102, 103, 106, 117 and 120are based on the entire solid including the sticky resin, lumpy mass andplate-like mass. The contents of these and the proportion of theparticles which passed through the 150 Tyler mesh sieve, based on thegranular or powdery product alone in the resulting solid, are given inthe parentheses in Table 11.

FIG. 2 shows an infrared absorption spectral chart of the granular orpowdery product obtained in Run No. 112, and also illustrates how todetermine t_(p) and t_(b), which are required in obtaining theabsorption intensity D, from the infrared absorption spectral chart. Abase line is drawn across a certain peak, and t_(p) and t_(b) can bedetermined at the wavelength of the peak as illustrated.

REFERENTIAL EXAMPLE 6

Ten kilograms of a mixed aqueous solution containing 18% by weight ofhydrochloric acid and 11% by weight of formaldehyde was put in each ofsix 20-liter reaction vessels in a room kept at a temperature of 21° to22° C. While the mixed aqueous solution was stirred at 23° C., a mixedaqueous solution containing 30% by weight of phenol, 20% by weight ofurea and 11% by weight of formaldehyde was added in an amount of 3.34kg, 2.66 kg, 1.60 kg, 1.06 kg, 0.74 kg, and 0.45 kg, respectively. Thebath ratio at this time was 7.0, 8.5, 13.5, 20.0, 28.0, and 45.0,respectively. In all runs, when the stirring was continued after theaddition of the mixed aqueous solution containing phenol, the mixtureabruptly became whitely turbid in 10 to 60 seconds. The stirring wasstopped as soon as the mixture became whitely turbid. The mixture wasthen left to stand for 3 hours. The temperature of the mixture graduallyrose, and in 30 minutes after it became whitely turbid, the formation ofa white slurry-like or resin-like product was observed. With stirring,the reaction mixture was washed with water. With the reaction mixtureobtained at a bath ratio of 7.0, a large amount of a resinous hardenedproduct melt-adhered to the stirring rod, and the stirring became verydifficult.

The contents of the reaction vessel were treated in a 0.3% by weightaqueous solution of ammonia at 30° C. for 2 hours with slow stirring,washed with water, and dehydrated. The resulting granular or powderyproduct or mass was lightly crumpled by hand, and dried at 40° C. for 3hours. After drying, the products had a water content of less than 0.5%by weight. The contents of the vessels are designated as Runs. Nos. 131,132, 133, 134, 135 and 136 in the increasing order of the bath ratio.

Table 12 summarizes the maximum temperature reached of the reactionsystem during the time from the initiation of the reaction of 3 hoursafter the reaction system became whitely turbid, the yield of thereaction product, the presence or absence of spherical primary particlesby microscopic observation, the proportion of particles which passedthrough a 150 Tyler mesh sieve, the bulk density of the particles whichpassed through the 150 Tyler mesh sieve, the heat fusibility of thereaction product at 100° C., the methanol solubility of the product, andthe free phenol content of the product.

                                      TABLE 12                                    __________________________________________________________________________                        Proportion of    Presence or                                    Maximum temper-                                                                             particles which                                                                        Bulk density of                                                                       absence of  Methanol                                                                           Free                          ature of the  passed through a                                                                       the 150 Tyler                                                                         spherical   solu-                                                                              phenol                  Run                                                                              Bath                                                                             reaction system                                                                        Yield                                                                              150 Tyler mesh                                                                         mesh under                                                                            primary                                                                             Flexibility                                                                         bility                                                                             content                 No.                                                                              ratio                                                                            reached (°C.)                                                                   (wt. %)                                                                            sieve (wt. %)                                                                          particles (g/cc)                                                                      particles                                                                           at 100° C.                                                                   (wt. %)                                                                            (ppm)                   __________________________________________________________________________    131                                                                               7.0                                                                             39.5     100  11       0.19    Little                                                                              Melt- 83.8 150                                                                adhered                            132                                                                               8.5                                                                             39.0     113  56       0.16    Much  Melt- 67.7 50                                                                 adhered                            133                                                                              13.5                                                                             38.0     124  88       0.14    Mostly                                                                              Melt- 60.4 35                                                                 adhered                            134                                                                              20.0                                                                             36.5     128  100      0.12    "     Melt- 53.6 30                                                                 adhered                            135                                                                              28.0                                                                             36.0     128  100      0.11    "     Melt- 54.4 25                                                                 adhered                            136                                                                              45.0                                                                             36.0     129  99       0.11    "     Melt- 52.6 25                                                                 adhered                             21                                                                              (Comparison;                                                                              --   --       0.62    None  Infusible                                                                           Not more                                                                           Below                      see Table 1)                                  than 1                                                                              5                       22                                                                              (Comparison;                                                                              --   --       0.46    "     Melt  1.6  Below                      see Table 1)                            adhered     5                       23                                                                              (Comparison;                                                                              --   --       0.24    --    Infusible                                                                           Not more                                                                           Below                      see Table 1)                                  than 1                                                                             5                       __________________________________________________________________________

In Table 12, the free phenol contents in Runs Nos. 21, 22 and 23 arevalues measured with regard to resol and novolak resins beforeheat-curing and are indicated in the parentheses.

In Run No. 131 shown in Table 12, a sticky resin and a lumpy mass formedin an amount of about 80% based on the entire solid formed at the bottomof the flask, and the proportion of the resulting granular or powderyproduct was only about 20% based on the entire solid. About 85% of suchgranular or powdery product passed through a 100 Tyler mesh sieve. The"little" in the column of the presence or absence of spherical primaryparticles indicated in Table 12 for Run No. 131 was because theproportion of the granular or powdery product based on the entire solidproduct was as small as about 20%. Hence, the method of Run No. 131cannot be recommended as a manufacturing method, but the resultinggranular or powdery product sufficiently has the properties of thegranular or powdery product suitably used in this invention.

Almost 100% of each of the granular or powdery products obtained in RunsNos. 131 to 136 consisted of particles having a particle size of 0.1 to100 microns.

REFERENTIAL EXAMPLE 7

A 2-liter separable flask was charged with 1,250 g of a mixed aqueoussolution at 24° C. containing 20% by weight of hydrochloric acid and 8%by weight of formaldehyde, and while it was stirred, a solution of eachof the phenols shown in Table 13 and each of the nitrogen compoundsshown in Table 13 diluted to a concentration of 20 to 80% by weight with37% by weight formalin was added so that the total amount of the phenoland the nitrogen-containing compound became 50 g. As soon as thesolution containing the phenol and the nitrogen-containing compound wereadded, the mixture became turbid, and in some Runs, instantaneouslyturned white, pink or brown. In 10 seconds after the addition of thesolution, the stirring was stopped. After the stopping of the addition,the mixture was allowed to stand for 60 minutes. Again with stirring, itwas heated to 75° C. over 30 minutes, and maintained at 73° to 76° C.for 60 minutes. The reaction product was washed with water, treated at45° C. for 60 minutes in a mixed aqueous solution containing 0.3% byweight of ammonia and 60% by weight of methanol, washed with water, andfinally dried at 80° C. for 3 hours.

Table 13 summarizes the types and proportions of the phenol and thenitrogen-containing compound used, the concentrations of the phenol andthe nitrogen-containing compound in the formalin-diluted solution, thecolor of the reaction product observed 60 minutes after the addition ofthe resulting diluted solution, the yield of the reaction product basedon the total amount of the phenol and the nitrogen-containing compound,the content of particles having a size of 0.1 l to 50 microns in thereaction product, the proportion of particles which passed through a 150Tyler mesh sieve, the D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio, and the heatresistance of the product.

                                      TABLE 13                                    __________________________________________________________________________                               Concentration                                                                          Color of the                              Proportion of the materials used (wt.)                                                                   of the material                                                                        reaction product                          Run           Nitrogen-containing                                                                        in the diluted                                                                         (60 minutes                               No.                                                                              Phenol     compound     solution (wt. %)                                                                       after addition)                           __________________________________________________________________________    137                                                                              Phenol 100 Urea 0       80       Pink                                      138                                                                              Phenol 97  Urea 3       "        "                                         139                                                                              Phenol 94  Urea 6       "        "                                         140                                                                              Phenol 75  Urea 25      50       Pale pink                                 141                                                                              Phenol 55  Urea 45      40       White color                               142                                                                              Phenol 35  Urea 64      30       "                                         143                                                                              Phenol 25  Urea 75      20       "                                         144                                                                              Phenol 10  Urea 90      20       "                                         145                                                                              Phenol 50  N,N'--dimethylolurea                                                                       50       "                                         146                                                                              Phenol 75  Aniline 25   80       Reddish brown                             147                                                                              Phenol 50  Melamine 50  "        White                                     148                                                                              Phenol 50  Urea 50      40       "                                         149                                                                              Phenol 50  Urea 50      "        Red                                       150                                                                              Phenol/resorcinol                                                                        Urea 33      40       Red                                          (= 34/33)                                                                  151                                                                              Phenol/t-butylphenol                                                                     Urea 40      "        Brown                                        (= 40/20)                                                                  152                                                                              Phenol 50  Urea/melamine (= 25/25)                                                                    50       White                                      21                                                                              Heat-cured resol resin                                                      22                                                                              Hexamine heat-cured novolak resin                                           23                                                                              Cured novolak fibers                                                       __________________________________________________________________________                   Proportion                                                             Contents of                                                                          of particles                                                           the particles                                                                        which passed             Heat                                          having a size                                                                        through a 150                                                                        IR intensity ratio                                                                              resis-                                Run                                                                              Yield                                                                              of 0.1 to 50                                                                         Tyler mesh                                                                           D.sub.1580-1650 /                                                                   D.sub.1280-1350 /                                                                   D.sub.960-1020 /                                                                    tance                                 No.                                                                              (wt. %)                                                                            microns (%)                                                                          sieve (wt. %)                                                                        D.sub.1450-1500                                                                     D.sub.1450-1500                                                                     D.sub.1450-1500                                                                     test (°C.)                     __________________________________________________________________________    137                                                                              118  91      98    0.25  0.18  0.44  750                                   138                                                                              108  90      98    0.27  0.18  0.31  420                                   139                                                                              112  97     100    0.57  0.21  0.30  280                                   140                                                                              128  100    100    1.24  0.95  0.19  200                                   141                                                                              132  100    100    1.32  1.10  0.29  "                                     142                                                                              115  100    100    1.37  1.08  0.29  "                                     143                                                                               76  100    100    1.37  0.99  0.30  "                                     144                                                                               31  100    100    1.24  0.96  0.27  "                                     145                                                                              105  94     100    1.19  0.88  0.38  "                                     146                                                                              101  82      88    1.21  1.03  0.20  "                                     147                                                                               86  100     96    1.15  0.75  0.28  "                                     148                                                                              109  100    100    1.31  1.02  0.27  "                                     149                                                                              100  72      83    1.33  0.99  0.26  "                                     150                                                                              132  91      94    1.25  0.99  0.25  200                                   151                                                                               84  96      96    1.16  0.96  0.19  "                                     152                                                                              102  95     100    1.24  1.01  0.30  "                                      21     17            0.22  0.10  0.03  720                                    22     58            0.50  0.13  3.73  610                                    23     39            0.15  0.08  0.14  740                                   __________________________________________________________________________

REFERENTIAL EXAMPLE 8

Each of six 1-liter separable flasks was charged with 1,000 g of a mixedaqueous solution at 18° C. containing 18% by weight of hydrochloric acidand 9% by weight of formaldehyde. The room temperature was 15° C. Whilethe solution was stirred, 15 g of urea was dissolved in it, and then 25g of a mixed diluted solution containing 80% by weight of phenol and 5%by weight of formaldehyde was added at a time. Ten seconds after theaddition of the diluted solution, the stirring was stopped, and thesolution was left to stand. In all Runs, the solution abruptly becamewhitely turbid in 18 to 19 seconds after the stopping of the stirring,and the formation of a milk-white product was observed. The temperatureof the solution gradually rose from 18° C., and reached a peak at31°-32° C. in 5 to 7 minutes after the addition of the diluted solutionof phenol, and then decreased. The flask was left to stand at roomtemperature for 0.5 hour (Run No. 161), 1 hour (Run No. 162), 3 hours(Run No. 163), 6 hours (Run No. 164), 24 hours (Run No. 165), and 72hours (Run No. 166), respectively, after the addition of the dilutedphenol solution. Then, the contents of the flask were treated in a 0.75%by weight aqueous solution of ammonia at 15° to 17° C. for 3 hours,washed with water, dehydrated, and finally dried at 40° C. for 6 hours.

Table 14 summarizes the proportion of particles which passed through a150 Tyler mesh sieve, the D₉₆₀₋₁₀₂₀ /D₁₄₅₀₋₁₅₀₀ ratio, the methanolsolubility, and the free phenol content of the resulting dried products.The samples obtained in Runs Nos. 161 to 166 all melt-adhered in afusibility test conducted at 100° C. for 5 minutes.

                                      TABLE 14                                    __________________________________________________________________________       Standing                                                                            Proportion of                                                           time at                                                                             particles which                                                         room tem-                                                                           passed through                                                                          Methanol                                                                           IR intensity ratio                                    Run                                                                              perature                                                                            a 150 Tyler                                                                             solubility                                                                         (D.sub.960-1020 /                                                                      Free phenol content                          No.                                                                              (hours)                                                                             mesh sieve (wt. %)                                                                      (wt. %)                                                                            D.sub.1450-1500)                                                                       (ppm)                                        __________________________________________________________________________    161                                                                              0.5   63        99.5 0.13     280                                          162                                                                              1     87        97.8 0.17     70                                           163                                                                              3     95        85.7 0.24     45                                           164                                                                              6     100       63.4 0.29     30                                           165                                                                              24    100       40.2 0.29     20                                           166                                                                              72    98        35.6 0.31     15                                           __________________________________________________________________________

REFERENTIAL EXAMPLE 9

A 1000-liter reaction vessel equipped with a stirring rod was chargedwith 800 kg of a mixed aqueous solution at 22.5° C. containing 18.5% byweight of hydrochloric acid and 8.5% by weight of formaldehyde, andwhile the mixed aqueous solution was stirred, 40 kg of a mixed aqueoussolution at 20° C. containing 20% by weight of phenol, 10% by weight ofhydroquinone and 20% by weight of urea was added.

After adding all of the phenol solution, the mixture was stirred for 20seconds. The stirring was stopped, and the mixture was left to stand for2 hours. In the reaction vessel, white suspended particles abruptlyformed in 35 seconds after the addition of all of the phenol solution. Awhite granular product gradually formed, and the temperature of thesuspension gradually rose to 35.5° C. and then decreased. The mixedaqueous solution in which the reaction product formed was again stirred,and a valve secured to the bottom of the reaction vessel was opened towithdraw the contents. By using a nonwoven fabric of Nomex (a tradenamefor a product of E. I. du Pont de Nemours & Co.), the contents wereseparated into the reaction product and the mixed aqueous solution ofhydrochloric acid and formaldehyde. The resulting reaction product waswashed with water, dehydrated, dipped for a day and night in a 0.5% byweight aqueous solution of ammonia at 18° C., again washed with water,and dehydrated to give 29.9 kg of the reaction product having a watercontent of 15% by weight.

2.0 kg of the reaction product thus obtained was dried at 40° C. for 3hours to give 1.7 kg of a sample (Run No. 167).

Table 15 gives the contents of particles having a size of 0.1 to 50microns and particles having a size of 0.1 to 100 microns determined bymicroscopic observation of the resulting dried sample, the proportion ofparticles which passed through a 150 Tyler mesh sieve, and the methanolsolubility of the product.

                  TABLE 15                                                        ______________________________________                                             Content of Content of Proportion                                              0.1-50     0.1-100    of particles                                                                             Methanol                                Run  micron     micron     150 mesh   solubility                              No.  particles (%)                                                                            particles (%)                                                                            under (wt. %)                                                                            (wt. %)                                 ______________________________________                                        167  100        100        99         58                                      ______________________________________                                    

EXAMPLE 5

One part by weight of chips of 6-nylon (1013B, a tradename for productof Ube Industries, Ltd.) was mixed with the granular or powdery resinobtained in Run No. 135 in an amount of 0, 0.015, 0.025, 0.04, 0.07,0.15, 0.4 and 0.8 part by weight, respectively. The mixture was kneadedand extruded by an extruder (Type 3AGM, made by Sumitomo HeavyIndustries, Ltd.), and cooled to produce guts. The guts were eachconverted to chips. Eight kinds of chips obtained were each molded in amold kept at 80° C. at a cylinder temperature of 250° C. to give eightkinds of molded articles each having a width of 5 cm, a length of 20 cmand a thickness of 0.5 cm (Runs Nos. 151 to 158).

Table 16 summarizes the flow of the mixed resin and the dispersibilityof the granular or powdery resin during extrusion molding, and thecompression strength and the volume inherent resistivity before or afterboiling in water of each of the molded articles.

                                      TABLE 16                                    __________________________________________________________________________                           Molded article                                         Amount (parts          Volume inherent                                        by (weight) of                                                                           Processibility                                                                            resistivity (ohm-cm)                                   Run                                                                              the product of                                                                        Flow of     Before                                                                             After                                                                              Compression                                  No.                                                                              Run No. 135                                                                           the resin                                                                          Dispersibility                                                                       boiling                                                                            boiling                                                                            strength (kg/mm.sup.2)                       __________________________________________________________________________    171                                                                              0       Excellent                                                                          --     10.sup.12                                                                          10.sup.9                                                                            8.7                                         172                                                                               0.015  Excellent                                                                          Good   10.sup.12                                                                          10.sup.10                                                                           9.5                                         173                                                                               0.025  Excellent                                                                          Excellent                                                                            10.sup.12                                                                          10.sup.11                                                                          11.3                                         174                                                                              0.04    Excellent                                                                          Excellent                                                                            10.sup.13                                                                          10.sup.12                                                                          13.2                                         175                                                                              0.07    Excellent                                                                          Excellent                                                                            10.sup.13                                                                          10.sup.13                                                                          15.6                                         176                                                                              0.15    Excellent                                                                          Excellent                                                                            10.sup.14                                                                          10.sup.14                                                                          17.8                                         177                                                                              0.4     Excellent                                                                          Excellent                                                                            10.sup.14                                                                          10.sup.14                                                                          17.0                                         178                                                                              0.8     Good Excellent                                                                            10.sup.14                                                                          10.sup.13                                                                          15.1                                         __________________________________________________________________________

EXAMPLE 6

One part by weight of a powder of 12-nylon (3035B, a tradename for aproduct of Ube Industries, Ltd.) was mixed with 0.3 part by weight ofeach of the products obtained in Runs Nos. 112, 140, 147 and 150, theproducts (cured products) obtained in Runs Nos. 21 to 23, and glassstaples (10 microns in diameter, and 2 mm in length). Each of themixtures was molded as in Example 5 to give 8 kinds of molded articles(Runs Nos. 170 to 186).

Table 17 shows the volume inherent resistivity before and after boilingin water and compression strength of the molded products, and themoldability of the mixed resin.

                                      TABLE 17                                    __________________________________________________________________________                       Volume inherent                                            Run                resistivity (ohm-cm)                                                                        Compression                                  No.                                                                              Material mixed                                                                        Moldability                                                                           Before boiling                                                                       After boiling                                                                        strength (kg/mm.sup.2)                       __________________________________________________________________________    179                                                                              Product of                                                                            Very good                                                                             10.sup.14                                                                            10.sup.13                                                                            13.8                                            Run No. 112                                                                180                                                                              Product of                                                                            Very good                                                                             10.sup.14                                                                            10.sup.14                                                                            14.9                                            Run No. 140                                                                181                                                                              Product of                                                                            Very good                                                                             10.sup.14                                                                            10.sup.13                                                                            12.6                                            Run No. 147                                                                182                                                                              Product of                                                                            Very good                                                                             10.sup.14                                                                            10.sup.13                                                                            13.1                                            Run No. 150                                                                183                                                                              Product of                                                                            Non-uniformity                                                                        10.sup.13                                                                            10.sup.10                                                                             7.3                                            Run No. 21                                                                            in dispersion                                                      184                                                                              Product of                                                                            Much gas                                                                              10.sup.12                                                                            10.sup.8                                                                              5.1                                            Run No. 22                                                                            generated                                                          185                                                                              Product of                                                                            Great non-                                                                            10.sup.13                                                                            10.sup.9                                                                              7.2                                            Run No. 23                                                                            uniformity                                                                    in dispersion                                                      186                                                                              Glass staples                                                                         Great non-                                                                            10.sup.13                                                                            10.sup.8                                                                              7.6                                                    uniformity                                                                    in dispersion                                                      __________________________________________________________________________

EXAMPLE 7

One part by weight of each of a polyester resin (BELLPET EFG-6, atradename for a product of Kanebo Synthetic Fibers Co., Ltd.), apolycarbonate resin (MAKROLON 3100, a tradename for a product of BayerAG), a polyethylene resin (Hizex 2000, a tradename for a product ofMitsui Petrochemical Industries, Ltd.), nylon-66 (Nylon 2020, atradename for a product of Ube Industries, Ltd.) and a vinyl chlorideresin (RYULON 7001, a tradename for a product of Tekkosha Co., Ltd.) wasmixed with 0.45 part by weight of the product of Run No. 164. Themixture was melted at a temperature of 150° to 300° C., and then cooledand cut. One hundred grams of each of the resulting samples was dividedinto ten equal portions, and treated for 5 minutes under a pressure of100 to 500 kg/cm² in a mold heated in advance to 100° to 250° C. betweenhot presses to obtain ten molded articles (width 13 mm, thickness5.2-6.8 mm, length 100 mm) from each of the samples (Runs Nos. 187 to191) shown in Table 18.

Table 18 shows the heat distortion temperature and combustibility (matchtest by contact with the flame of a match for 10 seconds) of each of themolded products as the average properties of the ten samples in eachRun. For comparison, molded articles were produced similarly from thevarious resins alone and the results are also shown in Table 18 (RunsNos. 192 to 196).

                  TABLE 18                                                        ______________________________________                                                              Heat                                                                          deform-                                                                       ation                                                                         temper-                                                                       ature     Combustibility to                             Run No.                                                                              Resin used     (°C.)                                                                            a match test                                  ______________________________________                                        Invention                                                                     187    Polyester resin                                                                              140       Self-extinguishing                            188    Polycarbonate resin                                                                          175       Flame-retardant,                                                              carbonized                                    189    Polyethylene resin                                                                            90       Burning very slow                             190    Nylon-66 resin 155       Flame-retardant,                                                              carbonized                                    191    Cinyl chloride 120       Flame-retardant,                                     resin                    carbonized                                    Comparison                                                                    192    Polyester resin                                                                               70       Burning slow                                  193    Polycarbonate resin                                                                          130       Self-extinguishing                            194    Polyethylene resin                                                                            55       Burning slow                                  195    Bylon-66 resin  70       Burning slow                                  196    Vinyl chloride  70       Self-extinguishing                                   resin                                                                  ______________________________________                                    

EXAMPLE 8

One part by weight of a powder of 12-nylon (3035J, a tradename for aproduct of Ube Industries, Ltd.) was mixed with 1, 3 or 10 parts byweight of the product of Run No. 167, and the mixture was treated undera pressure of 300 kg/cm² for 20 minutes in a mold heated in advance to150° to 170° C. between hot presses to produce ten molded plates (width13 mm, thickness 0.5-0.6 mm, length 100 mm) in each of Runs Nos. 197 to199 as shown in Table 19. For comparison, ten molded plates wereprepared from a powder of 12-nylon alone under the same conditions asabove except that a mold heated to 120° C. was used (Run No. 200).

Table 19 shows the heat shrinkage residual ratio of each of the moldedplates upon standing for 30 minutes in a desiccator at 200° C. in theair, the heat fusibility of each molded plate when it was maintained ina nitrogen atmosphere at 500° C. for 10 minutes, and the compressionstrength of each molded plate.

                  TABLE 19                                                        ______________________________________                                               Product of Heat                                                               Run No. 167                                                                              shrinkage        Compression                                       (parts by  residual  Heat   strength                                   Run No.                                                                              weight)    ratio (%) fusibility                                                                           (kg/mm.sup.2)                              ______________________________________                                        Invention                                                                     197    1          96.8      Heat-  15.2                                                                   infusible                                         198    3          99.0      Heat-  16.4                                                                   infusible                                         199    10         99.3      Heat-  19.7                                                                   infusible                                         Comparison                                                                    200    0          No shape  Fused   8.6                                                         retention                                                   ______________________________________                                    

EXAMPLE 9

Ten kinds of mixtures were prepared by mixing (1) 100 parts by weight ofNeoprene W (a tradename for a product of Showa Neoprene Co., Ltd.), 5parts by weight of zinc oxide, 4 parts by weight of highly activemagnesia, 3 parts by weight of light process oil, 1 part by weight ofstearic acid, 3 parts by weight of an accelerator (22) and 30 parts byweight of SRF black with (2) the granular or powdery resin obtained inRun No. 12 in an amount of 0, 1, 3, 5, 10, 50, 100, 150, 200, and 250parts by weight, respectively.

To each of the ten mixtures was added 2 times its amount oftrichloroethylene to dissolve it. The solution was fully stirred, andthe solvent was removed under a reduced pressure of 30 mmHg. Theresulting residue was cut to a size of 1 to 3 mm, placed in a mold (120mm×150 mm) heated in advance to 170° C., pressed while degassing, andfinally hot-pressed for 30 minutes under a pressure of 100 kg/cm² togive rubber sheets (Runs Nos. 251 to 260) shown in Table 20.

Table 20 summarizes the amount of the resin mixed; the thickness,hardness, compression set, tensile strength, tensile elongation andvolume inherent resistivity of the molded articles; and the hardness,tensile strength and tensile elongation of the molded articles afterheat-treatment at 170° C. for 24 hours.

                                      TABLE 20                                    __________________________________________________________________________    Amount of                            After heat-treatment                     the resin                                                                              Molded article              at 170° C. for 24 hours              mixed Thick-                                                                            Hard-                                                                             Compres-                                                                           Tensile                                                                            Elon-                                                                             Volume                                                                              Hard-                                                                             Tensile                                                                            Elon-                           Run                                                                              (parts by                                                                           ness                                                                              ness                                                                              sion strength                                                                           gation                                                                            resistivity                                                                         ness                                                                              strength                                                                           gation                          No.                                                                              weight)                                                                             (mm)                                                                              (°)                                                                        set (%)                                                                            (kg/cm.sup.2)                                                                      (%) (Ω-cm)                                                                        (°)                                                                        (kg/cm.sup.2)                                                                      (%)                             __________________________________________________________________________    251                                                                               0    1.1 76  16.3 73   370 6.2 × 10.sup.11                                                               78  62   106                             252                                                                               1    1.1 76  17.2 74   390 6.1 × 10.sup.11                                                               79  55   85                              253                                                                               3    1.2 79  8.9  82   260 1.1 × 10.sup.12                                                               83  86   105                             254                                                                               5    1.2 80  6.2  87   210 5.6 × 10.sup.12                                                               87  91   93                              255                                                                               10   1.3 83  5.3  105  170 1.3 × 10.sup.13                                                               90  116  74                              256                                                                               50   1.3 88  3.4  126  110 5.6 × 10.sup.13                                                               95  144  58                              257                                                                              100   1.3 90  3.0  101   80 7.8 × 10.sup.13                                                               96  120  51                              258                                                                              150   1.5 90  2.8  85    46 8.6 × 10.sup.13                                                               97  93   22                              259                                                                              200   1.7 89  3.7  31    25 2.1 × 10.sup.14                                                               94  54   13                              260                                                                              250   2.0 81   6.87                                                                               8    15 5.4 × 10.sup.13                                                               83  11    7                              __________________________________________________________________________

EXAMPLE 10

While 100 parts by weight of nitrile rubber (Hycar OR25, a tradename fora product of Japanese Zeon Co., Ltd.), 5 parts by weight of zinc oxide,1.5 parts by weight of stearic acid, 1.5 parts by weight of Altax, 3parts by weight of pine tar and 40 parts by weight of carbon black werekneaded on an open roll at 95° C., 10 parts by weight of each of theproducts of Runs Nos. 12, 44, 47, 21, 22 and 23 and wood flour wasadded. They were fully mixed and extruded into a rubber sheet. The sheetobtained was heat-treated at 170° C. under a pressure of 1 to 2 kg/cm²for 3 hours. The resulting rubber sheets so heat-treated had a thicknessof 1.0 to 1.1 mm and are designated as samples of Runs Nos. 261 to 268in the above-mentioned order of the fillers used.

Table 21 summarizes the types of the fillers used, and theirblendability, and the tensile strength and elongation of each of thesheets; and the shrinkage and tensile strength retention of the sheetsheat-treated at 180° C. for 24 hours.

                                      TABLE 21                                    __________________________________________________________________________                                After heat-treatment                                                 Tensile                                                                            Elon-                                                                             at 180° C. for 24 hours                    Run                strength                                                                           gation                                                                            Shrinkage                                                                           Strength                                    No.                                                                              Type of the filler                                                                     Blendability                                                                         (kg/cm.sup.2)                                                                      (%) (%)   retention (%)                               __________________________________________________________________________    261                                                                              None     --     73   420 4.1    95                                         262                                                                              Run No. 12                                                                             Very good                                                                            97   124 1.4   156                                         263                                                                              Run No. 44                                                                             Very good                                                                            91   154 1.2   168                                         264                                                                              Run No. 47                                                                             Very good                                                                            93   147 1.3   165                                         265                                                                              Run No. 21                                                                             Fair   86   340 1.7    91                                         266                                                                              Run No. 22                                                                             Good   62   380 3.4   108                                         267                                                                              Run No. 23                                                                             Fair   84   176 2.6   113                                         268                                                                              Wood flour                                                                             Slightly                                                                             55   280 3.1    75                                                     poor                                                              __________________________________________________________________________

EXAMPLE 11

One hundred parts by weight of each of the various rubbers shown inTable 22 was kneaded with 20 parts by weight of carbon black and thevarious compounding agents indicated in Table 24 at 50° to 110° C. usingan open roll. The kneaded mixture was extruded into a sheet form, andheat-treated at a temperature of 160° C. under a pressure of 0 to 1kg/cm² for 5 hours (16 hours in the case of fluorine rubber) to givevarious rubber sheets having a thickness of 0.9 to 1.1 mm.

Table 22 summarizes the types of the rubbers used, the types and amountsof the compounding agents, the hardness and tensile strength of each ofthe rubber sheets obtained, and the hardness, strength retention andshrinkage of each of the rubber sheets after heat-treatment at 150° C.for 24 hours.

The granular resin shown in the table was the one obtained in Run No. 35in Referential Example 2.

                                      TABLE 22                                    __________________________________________________________________________                 Amount of the         Rubber sheet                                                                            After heat-treatment                          granular resin             Tensile                                                                            at 150° C. for 24                                                      hours                            Run                                                                              Type of rubber                                                                          (parts by                                                                             Types and amounts (parts)                                                                   Hardness                                                                           strength                                                                           Hardness                                                                           Strength                                                                             Shrinkage            No.                                                                              (tradename)                                                                             weight) of the compounding agents                                                                   (°)                                                                         (kg/cm.sup.2)                                                                      (°)                                                                         retention                                                                            (%)                  __________________________________________________________________________    271                                                                              Natural rubber                                                                           0      Zinc oxide (5),                                                                             30   36   75    62    8.7                                       stearic acid (1)                                         272                                                                              Natural rubber                                                                          30      Accelerator M (1),                                                                          76   74   98   105    4.4                                       accelerator TT (1),                                                           sulfur (2)                                               273                                                                              Nitrile rubber                                                                           0      Zinc oxide (5),                                                                             61   68   67    96    2.8                     (Hycar OR)        stearic acid (1),                                                             pine tar (3)                                             274                                                                              Nitrile rubber                                                                          30      Accelerator DM (1),                                                                         88   66   94   153    1.4                     Hycar OR)         sulfur (2)                                               275                                                                              Butyl rubber                                                                             0      Zinc oxide (5),                                                                             63   68   69    89    3.7                     (GRI-50)          stearic acid (1),                                                             GMF (4)                                                  276                                                                              Butyl rubber                                                                            30      Lead oxide (5),                                                                             81   71   85   146    1.9                     (GRI-50)          sulfur (1)                                               277                                                                              Chlorinated poly-                                                                        0      Litharge (15), DOP (10),                                                                    72   61   81   102    2.4                     ethylene          accelerator 22 (4)                                          (ELASLEN 401A)                                                             278                                                                              Chlorinated poly-                                                                       30      TAIC (3), perhexa                                                                           83   72   87   140    1.4                     ethylene          3M-40 (5)                                                   (ELASLEN 401A)                                                             279                                                                              Chloroprene                                                                              0      Zinc oxide (5), stearic                                                                     76   80   94    96    1.8                     (Neoprene W)      acid (1), magnesia (4)                                   280                                                                              Chloroprene                                                                             30      Light process oil (1),                                                                      89   78   93   121    0.4                     (Neoprene W)      accelerator 22 (1)                                       281                                                                              Chlorosulfonated                                                                         0      Litharge (1.5),                                                                             76   76   83   100    2.9                     polyethylene      magnesia (10),                                              (Hypalon 40)      Tetron A (1)                                             282                                                                              Chlorosulfonated                                                                        30      Rosin ester (2)                                                                             84   85   87   128    1.1                     polyethylene                                                                  (Hypalon 40)                                                               283                                                                              Fluorine rubber                                                                          0      Magnesia (10), TET (2)                                                                      55   58   58   100    1.7                     (VITON B)                                                                  284                                                                              Fluorine rubber                                                                         30                    78   54   81   135    0.9                     (VITON B)                                                                  285                                                                              Styrene-butadiene                                                                        0      Zinc oxide (5),                                                                             77   67   87    85    5.6                     rubber (JSR 1502) stearic acid (1),                                        286                                                                              Styrene-butadiene                                                                       30      accelerator DM (1.5),                                                                       86   65   94   109    3.3                     rubber (JSR 1502) accelerator TT (1),                                                           sulfur (2)                                               __________________________________________________________________________

EXAMPLE 12

Ten kinds of mixtures were prepared by mixing (1) 100 parts by weight ofNeoprene W (a tradename for a product of Showa Neoprene Co., Ltd.), 5parts by weight of zinc oxide, 4 parts by weight of highly activemagnesia, 3 parts by weight of light process oil, 1 part by weight ofstearic acid, 3 parts by weight of an accelerator (22) and 30 parts byweight of SRF black with (2) the granular or powdery resin obtained inRun No. 112 in an amount of 0, 1, 3, 5, 10, 50, 100, 150, 200, and 250parts by weight, respectively.

To each of the ten mixtures was added 2 times its amount oftrichloroethylene to dissolve it. The solution was fully stirred, andthe solvent was removed under a reduced pressure of 30 mmHg. Theresulting residue was cut to a size of 1 to 3 mm, placed in a mold (120mm×150 mm) heated in advance to 170° C., pressed while degassing, andfinally hot-pressed for 30 minutes under a pressure of 100 kg/cm² togive rubber sheets (Runs Nos. 368 to 377) shown in Table 23.

Table 23 summarizes the amount of the resin mixed; the thickness,hardness, compression set, tensile strength, tensile elongation andvolume inherent resistivity of the molded articles; and the hardness,tensile strength and tensile elongation of the molded articles afterheat-treating at 200° C. for 8 hours.

                                      TABLE 23                                    __________________________________________________________________________    Amount of                            After heat-treatment                     the resin                                                                              Molded article              at 200° C. for 8 hours               mixed Thick-                                                                            Hard-                                                                             Compres-                                                                           Tensile                                                                            Elon-                                                                             Volume                                                                              Hard-                                                                             Tensile                                                                            Elon-                           Run                                                                              (parts by                                                                           ness                                                                              ness                                                                              sion strength                                                                           gation                                                                            resistivity                                                                         ness                                                                              strength                                                                           gation                          No.                                                                              weight)                                                                             (mm)                                                                              (°)                                                                        set (%)                                                                            (kg/cm.sup.2)                                                                      (%) (Ω-cm)                                                                        (°)                                                                        (kg/cm.sup.2)                                                                      (%)                             __________________________________________________________________________    368                                                                               0    1.1 76  16.3 73   370 6.2 × 10.sup.11                                                               81  48   40                              369                                                                               1    1.1 76  15.9 69   360 5.8 × 10.sup.11                                                               80  36   35                              370                                                                               3    1.1 79  9.6  81   310 1.0 × 10.sup.12                                                               84  83   75                              371                                                                               5    1.1 80  7.1  84   280 7.8 × 10.sup.12                                                               86  87   90                              372                                                                               10   1.2 82  4.8  101  220 1.9 × 10.sup.13                                                               88  107  125                             373                                                                               50   1.3 85  3.3  118  160 3.7 × 10.sup.13                                                               90  132  110                             374                                                                              100   1.3 88  2.6  105  130 4.8 ×  10.sup.13                                                              92  111  85                              375                                                                              150   1.4 89  2.6  82    65 7.4 × 10.sup.13                                                               95  96   40                              376                                                                              200   1.5 89  3.9  47    30 9.6 × 10.sup.13                                                               94  51   25                              377                                                                              250   1.8 78  7.4  11    20 6.7 × 10.sup.13                                                               87  15   10                              __________________________________________________________________________

EXAMPLE 13

While 100 parts by weight of nitrile rubber (Hycar OR25, a tradename fora product of Japanese Zeon Co., Ltd.), 5 parts by weight of zinc oxide,1.5 parts by weight of stearic acid, 1.5 parts by weight of Altax, 3parts by weight of pine par, 1 part by weight of an accelerator (DM) and2 parts by weight of sulfur, and 40 parts by weight of carbon black werekneaded on an open roll at 95° C., 40 parts by weight of each of theproducts of Runs Nos. 113, 134, 140, 147, 150, 163, 167, 21, 22 and 23and wood flour was added as a filler. They were fully mixed and extrudedinto a rubber sheet. The sheet obtained was heat-treated at 170° C.under a pressure of 1 to 2 kg/cm² for 3 hours. The resulting rubbersheets so heat-treated had a thickness of 1.0 to 1.2 mm and aredesignated as samples of Runs Nos. 379 to 389 in the order of thefillers used, and Run No. 379 in which no filler was used.

Table 24 summarizes the types of the fillers used, and theirblendability, and the tensile strength and elongation of each of thesheets; and the shrinkage and tensile strength retention of the sheetsheat-treated at 180° C. for 24 hours.

                                      TABLE 24                                    __________________________________________________________________________                                 After heat-treatment                                                 Tensile                                                                            Elon-                                                                             at 180° C. for 24 hours                   Run           Blend-                                                                              strength                                                                           gation                                                                            Shrinkage                                                                           Strength re-                               No.                                                                              Type of the filler                                                                       ability                                                                             (kg/cm.sup.2)                                                                      (%) (%)   tention (%)                                __________________________________________________________________________    378                                                                              None       --    73   420 4.1    95                                        379                                                                              Product of Run No. 113                                                                   Very good                                                                           86   175 1.6   141                                        380                                                                              Product of Run No. 134                                                                   Very good                                                                           105  140 1.3   165                                        381                                                                              Product of Run No. 140                                                                   Very good                                                                           87   180 1.7   146                                        382                                                                              Product of Run No. 147                                                                   Very good                                                                           93   190 1.7   151                                        383                                                                              Product of Run No. 150                                                                   Very good                                                                           84   170 1.5   146                                        384                                                                              Product of Run No. 163                                                                   Very good                                                                           112  130 1.1   160                                        385                                                                              Product of Run No. 167                                                                   Very good                                                                           108  105 1.2   174                                        386                                                                              Powder of Run No. 21                                                                     Fair  86   340 1.7    91                                        387                                                                              Product of Run No. 22                                                                    Good  62   380 3.4   108                                        388                                                                              Powder of Run No. 23                                                                     Fair  84   176 2.6   113                                        389                                                                              Wood flour Slightly                                                                            55   280 3.1    75                                                      poor                                                            __________________________________________________________________________

EXAMPLE 14

One hundred parts by weight of each of the various rubbers shown inTable 25 was kneaded with 20 parts by weight of carbon black and thevarious compounding agents indicated in Table 25 at 50° to 110° C. usingan open roll. The kneaded mixture was extruded into a sheet form, andheat-treated at a temperature of 160° C. under a pressure of 0 to 2kg/cm² for 5 hours (16 hours in the case of fluorine rubber) to givevarious rubber sheets having a thickness of 0.9 to 1.2 mm.

Table 25 summarizes the types of the rubbers used, the types and amountsof the compounding agents, the hardness and tensile strength of each ofthe rubber sheets obtained, and the hardness, strength retention andshrinkage of each of the rubber sheets after heat-treatment at 150° C.for 24 hours.

The granular resin shown in the table was the one obtained in Run No.164 in Referential Example 8.

                                      TABLE 25                                    __________________________________________________________________________                                        Rubber sheet                                                                            After heat-treatment                         Amount of the               Tensile                                                                            at 150° C. for 24                                                      hours                           Run                                                                              Type of rubber                                                                          granular resin                                                                         Types and amounts (parts)                                                                   Hardness                                                                           strength                                                                           Hardness                                                                           Strength                                                                             shrinkage           No.                                                                              (tradename)                                                                             (parts by weight)                                                                      of the compounding agents                                                                   (°)                                                                         (kg/cm.sup.2)                                                                      (°)                                                                         retention                                                                            (%)                 __________________________________________________________________________    390                                                                              Natural rubber                                                                           0       Zinc oxide (5),                                                                             30   36   75    62    8.7                 391                                                                              Natural rubber                                                                          30       stearic acid (1),                                                                           71   87   94   113    4.6                                       accelerator M (1),                                                            accelerator TT (1),                                                           sulfur (2)                                              392                                                                              Nitrile rubber                                                                           0       Zinc oxide (5),                                                                             61   68   67    96    2.8                    (Hycar OR)         stearic acid (1),                                       393                                                                              Nitrile rubber                                                                          30       pine tar (3), 84   79   91   147    1.3                    (Hycar OR)         accelerator DM (1),                                                           sulfur (2)                                              394                                                                              Butyl rubber                                                                             0       Zinc oxide (5),                                                                             63   68   69    89    3.7                    (GRI-50)           stearic acid (1),                                       395                                                                              Butyl rubber                                                                            30       GMF (4),      77   85   84   133    1.6                    (GRI-50)           lead oxide (5),                                                               sulfur (1)                                              396                                                                              Chlorinated                                                                              0       Litharge (15),                                                                              72   61   81   102    2.4                    polyethylene       DOP (10),                                                  (ELASLEN 401A)     accelerator 22 (4),                                     397                                                                              Chlorinated                                                                             30       TAIC (3),     80   92   82   155    1.2                    polyethylene       perhexa 3M-40 (5)                                          (ELASLEN 401A)                                                             398                                                                              Chloroprene                                                                              0       Zinc oxide (5),                                                                             76   80   94    96    1.8                    (Neoprene W)       stearic acid (1),                                       399                                                                              Chloroprene                                                                             30       magnesia (4), 83   96   89   136    0.6                    (Neoprene W)       light process oil (1),                                                        accelerator 22 (1)                                      400                                                                              Chlorosulfonated                                                                         0       Litharge (1.5),                                                                             76   76   83   100    2.9                    polyethylene       magnesia (10),                                             (Hypalon 40)                                                               401                                                                              Chlorosulfonated                                                                        30       Tetron A (1), 80   102  86   147    1.3                    polyethylene       rosin ester (2)                                            (Hypalon 40)                                                               402                                                                              Fluorine rubber                                                                          0       Magnesia (10),                                                                              55   58   58   100    1.7                    (Viton B)          TET (2)                                                 403                                                                              Fluorine rubber                                                                         30                     73   76   79   154    0.9                    (Viton B)                                                                  404                                                                              Styrene-   0       Zinc oxide (5),                                                                             77   67   87    85    5.6                    butadiene          stearic acid (1),                                          rubber             accelerator TT (1),                                        (JSR 1502)         sulfur (2)                                              405                                                                              Styrene-  30       sulfur (2)    81   80   91   120    2.5                    butadiene                                                                     rubber                                                                        (JSR 1502)                                                                 __________________________________________________________________________

EXAMPLE 15

Sixty parts by weight of the product of Run No. 43 (as a matrix) wasmixed with 40 parts by weight of each of glass staples (Run No. 551) cutto a size of 3 mm, rock wool (Run No. 552), carbon black (Run No. 553),hollow microspheres (Run No. 554), wood flour (Run No. 555), kraft pulp(Run No. 556) and 6-nylon staples (Run No. 557) cut to a size of 3 mm. Apredetermined amount of the mixture was put in a mold heated to atemperature of 120° C. using a press and treated under a pressure of 300kg/cm° for 30 minutes to give ten molded test pieces having a width of12 mm, a length of 100 mm and a thickness of 4.8 to 5.1 mm in each Run.Similarly, ten molded test pieces were prepared under the sameconditions as above using 60 parts by weight of the product of Run No.47 (as a matrix) and 47 parts by weight of the glass staples (Run No.558) and wood flour (Run No. 559). For comparison, 60 parts by weight,as solids, of the uncured resol resin used in Run No. 21 (as a matrix)as a solution was mixed with 40 parts by weight of each of glass staples(Run No. 560) cut to 3 mm, rock wool (Run No. 561), carbon black (RunNo. 562), hollow microspheres (Run No. 563), wood flour (Run No. 564),kraft pulp (Run No. 565) and 6-nylon staples cut to 3 mm (Run No. 566).The mixture was dried in the air at room temperature for 24 hours, andthen dried at 80° C. for 30 minutes to remove the solvent. Apredetermined amount of the resulting mixture was treated under apressure of 300 kg/cm² for 30 mimutes in a mold heated in advance to150° C. using a press to give ten molded test samples each having awidth of 12 mm, a length of 100 mm and a thickness of 3.0 to 3.2 mm ineach run.

Table 26 shows the types of the matrices and fillers used, the averageflexural strength of five molded samples, and the heat-resistanttemperatures of the molded samples.

                  TABLE 26                                                        ______________________________________                                                                              Heat-                                                                  Flexural                                                                             resistant                               Run  Type of      Type of      strength                                                                             tempera-                                No.  the matrix   the filler   (kg/cmp.sup.2)                                                                       ture (°C.)                       ______________________________________                                        551  Product of   Glass staples                                                                              880    210                                          Run No. 43                                                               552  Product of   Asbestos     670    190                                          Run No. 43                                                               553  Product of   Carbon black 520    220                                          Run No. 43                                                               554  Product of   Hollow       510    210                                          Run No. 43                                                               555  Product of   Wood flour   460    170                                          Run No. 43                                                               556  Product of   Kraft pulp   650    170                                          Run No. 43                                                               557  Product of   6-Nylon staples                                                                            770    150                                          Run No. 43                                                               558  Product of   Glass staples                                                                              830    210                                          Run No. 47                                                               559  Product of   Wood flour   470    170                                          Run No. 47                                                               560  Resol resin  Glass staples                                                                              650    180                                          of Run No. 21                                                            561  Resol resin  Asbestos     460    160                                          of Run No. 21                                                            562  Resol resin  Carbon black 440    180                                          of Run No. 21                                                            563  Resol resin  Hollow       290    190                                          of Run No. 21                                                                              microspheres                                                564  Resol resin  Wood flour   320    150                                          of Run No. 21                                                            565  Resol resin  Kraft pulp   470    140                                          of Run No. 21                                                            566  Resol resin  6-Nylon staples                                                                            570    120                                          of Run No. 21                                                            ______________________________________                                    

In Runs Nos. 551 to 559, molding could be performed without any trouble,but in Runs Nos. 560 to 566, the flow of the resin was poor and muchgases were generated, thus showing poor moldability.

EXAMPLE 16

In accordance with the method of Example 15, 30 parts by weight of theproduct of Run No. 12 (as a filler), 25 parts by weight of glass staplescut to a size of 2 mm (as a filler) and 45 parts by weight of each ofthe uncured resol resin used in Run No. 21, the novolak resin used inRun No. 22 (containing 15 parts by weight of hexamine), a furan resin(Hitafuran 303, a tradename for a product of Hitachi Chemical, Limited),an epoxy resin (Epikote 815, a tradename for a product of Shell ChemicalCo.) and a melamine resin (MERUMAITE, a tradename for a product of ToyoKoatsu Co., Ltd.) as a matrix (Runs Nos. 571 to 575 in this order ofmatrices) were mixed in the form of a powder or solution. Apredetermined amount of each of the resulting mixtures was molded at atemperature of 150° to 170° C. under a pressure of 200 to 400 kg/cm² for30 minutes using a hot press and a mold in accordance with Example 1 togive five test samples for measurement of compression strength eachhaving a width of 10 mm, a length of 10 mm and a thickness of 3.5 to 3.6mm and five test samples for measurement of heat conductivity eachhaving a width of 100 mm, a length of 100 mm and a thickness of 4.9 to5.1 mm.

As controls, test samples were prepared in the same way as above using55 parts by weight of glass fibers cut to a length of 2 mm, and 45 partsby weight of each of the uncured resol resin used in Run No. 21, thenovolak resin used in Run No. 22 (containing 15 parts by weight ofhexamethylenetetramine), the furan resin, the epoxy resin and themelamine resin (Runs Nos. 576 to 580).

Table 27 summarizes the types and amounts of the fillers used, the typesof the matrices (45 parts by weight), and the average compressionstrength and heat conductivity values of the molded articles.

                                      TABLE 27                                    __________________________________________________________________________    Filler (parts by weight)                                                           Product of                                                                           Glass                                                                              Matrix resin (45                                                                      Compression                                                                            Heat conductivity                           Run No.                                                                            Run No. 12                                                                           fibers                                                                             parts by weight)                                                                      strength (kg/cm.sup.2)                                                                 (cal/cm.sec. °C.)                    __________________________________________________________________________    571  30     26   Resol resin                                                                           2,430     5.7 × 10.sup.-4                      572  30     25   Novolak resin                                                                         2,040     6.2 × 10.sup.-4                      573  30     25   Furan resin                                                                           1,720     6.8 × 10.sup.-4                      574  30     25   Epoxy resin                                                                           1,530     6.5 × 10.sup.-4                      575  30     252  Melamine resin                                                                        1,460     9.1 × 10.sup.-4                      576  Not used                                                                             55   Resol resin                                                                           1,780    10.4 × 10.sup.-4                      577  Not used                                                                             55   Novolak resin                                                                         1,270    10.8 × 10.sup.-4                      578  Not used                                                                             55   Furan resin                                                                           1,040    10.9 × 10.sup.-4                      579  Not used                                                                             55   Epoxy resin                                                                           1,150    11.1 × 10.sup.-4                      580  Not used                                                                             55   Melamine resin                                                                          940    14.6 × 10.sup.-4                      __________________________________________________________________________

As in Runs Nos. 576 to 580, an attempt was made to obtain a moldedarticle by using 25 parts by weight of glass fibers and 75 parts byweight of each of the matrix resins without the product of Run No. 12.But the moldability was poor and molded articles of satisfactory qualitycould not be obtained.

EXAMPLE 17

The uncured resol resin solution used in Run No. 21 was mixed with theproduct of Run No. 35 as a filler in various proportions. The mixtureswere each dried in the air at room temperature for 48 hours, and furthertreated at 70° C. for 60 minutes. A molding mixture was prepared in thesame way as above from the aforesaid resol resin solution and each ofthe powders obtained in Runs Nos. 21 and 22.

Each of the mixtures was molded at a temperature of 150° to 180° C.under a pressure of 200 kg/cm² to prepare 15 test samples having a widthof 12 mm, a length of 100 mm and a thickness of 3.0 to 3.5 mm in eachrun.

Table 28 summarizes the amounts of the resol resin (solids), the productof Run No. 35 and the powders of Runs Nos. 21 and 22, the moldability ofeach of the mixtures, and the heat resistant temperatures and volumeresistivities of the molded articles.

                                      TABLE 28                                    __________________________________________________________________________               Filler            Molded article                                        Resol resin Amount      Heat     Volume                                       (parts by   (parts by   resistant                                                                              resistivity                             Run No.                                                                            weight)                                                                             Type  weight)                                                                            Moldability                                                                          temperature (°C.)                                                               (ohm-cm)                                __________________________________________________________________________    581  100   Product of                                                                           0   Very difficult                                                                       150      10.sup.13                                          Run No. 35                                                         582  85    Product of                                                                          15   Good   180      10.sup.14                                          Run No. 35                                                         583  75    Product of                                                                          25   Very good                                                                            210      10.sup.14                                          Run No. 35                                                         584  65    Product of                                                                          35   Very good                                                                            230      10.sup.14                                          Run No. 35                                                         585  50    Product of                                                                          50   Very good                                                                            240      10.sup.14                                          Run No. 35                                                         586  50    Powder of                                                                           50   Difficult                                                                            160      10.sup.11                                          Run No. 21                                                         587  50    Powder of                                                                           50   Good   140      10.sup.12                               __________________________________________________________________________

EXAMPLE 18

Sixty parts by weight of the product of Run No. 135 (as a matrix) wasmixed with 40 parts by weight of each of glass staples (Run No. 671) cutto a size of 3 mm, rock wool (Run No. 672), carbon black (Run No. 673),hollow microspheres (Run No. 674), wood flour (Run No. 675), kraft pulp(Run No. 676), 6-nylon staples (Run No. 677) cut to a size of 3 mm, andKevlar staples (Run No. 678) cut to a size of 3 mm. A predeterminedamount of the mixture was put in a mold heated to a temperature of 120°C. using a press and treated under a pressure of 250 to 350 kg/cm² for30 minutes to give ten molded test pieces having a width of 12 mm, alength of 100 mm and a thickness of 3.5 to 3.8 mm in each run.Similarly, ten molded test samples were prepared under the sameconditions as above from each of mixtures prepared from 60 parts byweight of the product of Run No. 163 (as a matrix) and 40 parts byweight of the glass staples (Run No. 679), the wood flour (Run No. 680)and the 6-nylon staples (Run No. 681), respectively, and mixturesprepared from 60 parts by weight of the product of Run No. 167 (as amatrix) and 40 parts by weight of the glass staples (Run No. 682), thewood flour (Run No. 683) and the 6-nylon staples (Run No. 684),respectively.

For comparison, 60 parts by weight of the uncured resol resin (as amatrix) used in Run No. 21 as a solution was mixed with 40 parts byweight of each of glass staples (Run No. 685) cut to a size of 3 mm,rock wool (Run No. 686), carbon black (Run No. 687), hollow microspheres(Run No. 688), wood flour (Run No. 689), kraft pulp (Run No. 690),6-nylon staples (Run No. 691) cut to a size of 3 mm and Kevlar staples(Run No. 692) cut to a size of 3 mm. The mixture was dried in the air atroom temperature for 24 hours, and then dried at 80° C. for 30 minutesto remove the solvent. A predetermined amount of the resulting mixturewas treated under a pressure of 250 to 350 kg/cm² for 30 minutes in amold heated in advance to 150° C. using a press to give ten molded testsamples each having a width of 12 mm, a length of 100 mm and a thicknessof 3.0 to 3.2 mm in each run.

Table 29 shows the types of the matrices and fillers used, the averageflexural strength of five molded samples, and the heat-resistanttemperatures of the five molded samples.

                  TABLE 29                                                        ______________________________________                                                                              Heat-                                                                  Flexural                                                                             resistant                               Run  Type of      Type of      strength                                                                             tempera-                                No.  the matrix   the filler   (kg/cm.sup.2)                                                                        ture (°C.)                       ______________________________________                                        671  Product of   Glass staples                                                                              1.030  220                                          Run No. 135                                                              672  Product of   Rock wool    780    190                                          Run No. 135                                                              673  Product of   Carbon black 640    230                                          Run No. 135                                                              674  Product of   Hollow       600    220                                          Run No. 135  microspheres                                                675  Product of   Wood flour   510    170                                          Run No 135                                                               676  Product of   Kraft pulp   690    180                                          Run No. 135                                                              677  Product of   6-Nylon staples                                                                            870    170                                          Run No. 135                                                              678  Product of   Glass staples                                                                              1,210  200                                          Run No. 135                                                              679  Product of   Kelvar fibers                                                                              1,140  230                                          Run No. 163                                                              680  Product of   Wood flour   630    170                                          Run No. 163                                                              681  Product of   6-Nylon staples                                                                            770    180                                          Run No. 163                                                              682  Product of   Glass staples                                                                              1,090  220                                          Run No. 167                                                              683  Product of   Wood flour   540    180                                          Run No. 167                                                              684  Product of   6-Nylon staples                                                                            810    160                                          Run No. 167                                                              685  Resol resin  Glass staples                                                                              650    180                                          of Run No. 21                                                            686  Resol resin  Rock wool    460    160                                          of Run No. 21                                                            687  Resol resin  Carbon black 440    180                                          of Run No. 21                                                            688  Resol resin  Hollow       290    190                                          of Run No. 21                                                                              microspheres                                                689  Resol resin  Wood flour   320    150                                          of Run No. 21                                                            690  Resol resin  Kraft pulp   470    140                                          of Run No. 21                                                            691  Resol resin  6-Nylon staples                                                                            570    120                                          of Run No. 21                                                            692  Resol resin  Kelvar fibers                                                                              780    120                                          of Run No. 21                                                            ______________________________________                                    

In Runs Nos. 671 to 684, molding could be performed easily without anytrouble. But in Runs Nos. 685 to 692, the flow of the resin compositionwas poor, or the resol resin melted away from the mold. Furthermore,much gases were generated to degrade moldability.

EXAMPLE 19

In accordance with the method of Example 18, 30 parts by weight of theproduct of Run No. 140 (as a filler), 25 parts by weight of glassstaples cut to a size of 2 mm (as a filler) and 45 parts by weight ofeach of the uncured resol resin used in Run No. 21, the novolak resinused in Run No. 22 (containing 15 parts by weight of hexamine), a furanresin (Hitafuran 303, a tradename for a product of Hitachi Chemical,Limited), an epoxy resin (Epikote 815, a tradename for a product ofShell Chemical Co.) and a melamine resin (MERVMAITE, a tradename for aproduct of Toyo Koatsu Co., Ltd.) as a matrix (Runs Nos. 693 to 697 inthis order of matrices) were mixed in the form of a powder or solution.A predetermined amount of each of the resulting mixtures was molded at atemperature of 150° to 170° C. under a pressure of 200 to 400 kg/cm² for30 minutes using a hot press and a mold in accordance with Example 18 togive five test samples for measurement of compression strength eachhaving a width of 10 mm, a length of 10 mm and a thickness of 3.3 to 3.7mm and five test samples for measurement of heat conductivity eachhaving a width of 100 mm, a length of 100 mm and a thickness of 4.7 to5.1 mm. Similarly, test samples were prepared as above using the productof Run No. 147 (as a filler and the product of Run No. 150 (as a filler)(Runs Nos. 698 to 707).

As controls, test samples were prepared in the same way as above using55 parts by weight of glass fibers cut to a length of 2 mm, and 45 partsby weight of each of the uncured resol resin used in Run No. 21, thenovolak resin used in Run No. 22 (containing 15 parts by weight ofhexamethylenetetramine), the furan resin, the epoxy resin and themelamine resin (Runs Nos. 708 to 712).

Table 30 summarizes the types and amounts of the fillers used, the typesof the matrices (45 parts by weight), and the average compressionstrength and heat conductivity values of the molded articles.

                                      TABLE 30                                    __________________________________________________________________________    Filler (parts by weight)                                                                         Type of the matrix                                                                      CompressioN                                           Type of the filler                                                                      Glass                                                                             (45 parts strength                                                                             Heat conductivity                         Run No.                                                                            (30 parts by weight)                                                                    fibers                                                                            by weight)                                                                              (kg/cm.sup.2)                                                                        (cal/cm · sec.°           __________________________________________________________________________                                        C.)                                       693  Product of                                                                              25  Resol resin                                                                             2,640  6.1 × 10.sup.-4                          Run No. 140                                                              694  Product of                                                                              25  Novolak resin                                                                           2,050  6.9 × 10.sup.-4                          Run No. 140                                                              695  Product of                                                                              25  Furan resin                                                                             1,920  7.6 × 10.sup.-4                          Run No. 140                                                              696  Product of                                                                              25  Epoxy resin                                                                             1,680  7.2 × 10.sup.-4                          Run No. 140                                                              697  Product of                                                                              25  Melamine  1,590  10.3 × 10.sup.-4                         Run No. 140   resin                                                      698  Product of                                                                              25  Resol resin                                                                             2,210  7.4 × 10.sup.-4                          Run No. 147                                                              699  Product of                                                                              25  Novolak resin                                                                           1,870  6.9 × 10.sup.-4                          Run No. 147                                                              700  Product of                                                                              25  Furan resin                                                                             1,550  8.6 × 10.sup.-4                          Run No. 147                                                              701  Product of                                                                              25  Epoxy resin                                                                             1,440  8.5 × 10.sup.-4                          Run No. 147                                                              702  Product of                                                                              25  Melamine  1,230  11.3 × 10.sup.-4                         Run No. 147   resin                                                      703  Product of                                                                              25  Resol resin                                                                             2,390  5.4 × 10.sup.-4                          Run No. 150                                                              704  Product of                                                                              25  Novolak resin                                                                           2,110  6.7 × 10.sup.-4                          Run No. 150                                                              705  Product of                                                                              25  Furan resin                                                                             1,860  7.4 × 10.sup.-4                          Run No. 150                                                              706  Product of                                                                              25  Epoxy resin                                                                             1,540  6.8 × 10.sup.-4                          Run No. 150                                                              707  Product of                                                                              25  Melamine  1,470  9.7 × 10.sup.-4                          Run No. 150   resin                                                      708  Not used  55  Resol resin                                                                             1,780  10.4 × 10.sup.-4                    709  Not used  55  Furan resin                                                                             1,040  10.9 × 10.sup.-4                    710  Not used  55  Epoxy resin                                                                             1,150  11.1 × 10.sup.-4                    711  Not used  55  Epoxy resin                                                                             1,150  11.1 × 10.sup.-4                    712  Not used  55  Melamine    940  14.6 × 10.sup.-4                    __________________________________________________________________________

As in Runs Nos. 708 to 712, an attempt was made to obtain moldedarticles by using 25 parts by weight of glass staples and 75 parts byweight of each of the matrix resins without the product of Run No. 140,or the product of Run No. 147 or the product of Run No. 150. But thematrix resin flowed out from the mold or foamed, so that molded articlesof satisfactory quality could not be obtained.

EXAMPLE 20

The uncured resol resin solution used in Run No. 21 was mixed with theproduct of Run No. 112 as a filler in various proportions. Each of themixtures was dried in the air at room temperature for 48 hours, andfurther treated at 70° C. for 60 minutes. Molding mixtures were preparedin the same way as above from the aforesaid resol resin solution and thepowders of Runs nos. 21 and 22 as fillers.

Each of the molding mixtures obtained was molded at 150° to 180° C. and200 kg/cm² using a press and a mold to give 15 test samples each havinga width of 12 mm, a length of 100 mm and a thickness of 3.0 to 3.5 mm ineach run.

Table 31 summarizes the amounts of the resol resin (solids), the productof Run No. 112, the powder of Run No. 21 and the powder of Run No. 22,the moldability of each of the molding mixtures, and the heat resistanttemperatures and volume resistivities before or after boiling of theresulting molded products.

                                      TABLE 31                                    __________________________________________________________________________                                    Molded article                                                                Heat Volume                                   Resol resin                                                                              Filler               resistant                                                                          resistivity (ohm-cm)                          (parts by    Amount (parts tempera-                                                                           Before                                                                             After                               Run No.                                                                            weight)                                                                             Type   by weight)                                                                           Moldability                                                                          ture (°C.)                                                                  boiling                                                                            boiling                             __________________________________________________________________________    713  100   Product of                                                                            0     Very difficult                                                                       150  10.sup.14                                                                          10.sup.5                                       resin No. 112                                                      714  85    Product of                                                                           15     Good   180  10.sup.14                                                                          10.sup.12                                      resin No. 112                                                      715  75    Product of                                                                           25     Very good                                                                            220  10.sup.14                                                                          10.sup.13                                      resin No. 112                                                      716  65    Product of                                                                           35     "      240  10.sup.14                                                                          10.sup.14                                      resin No. 112                                                      717  50    Product of                                                                           50     "      250  10.sup.13                                                                          10.sup.13                                      resin No. 112                                                      718  40    Product of                                                                           60     "      250  10.sup.13                                                                          10.sup.13                                      resin No. 112                                                      719  50    Powder of                                                                            50     Difficult                                                                            160  10.sup.14                                                                          10.sup.8                                       Run No. 21                                                         720  50    Powder of                                                                            50     Good   140  10.sup.13                                                                          10.sup.9                                       Run No. 22                                                         __________________________________________________________________________

The test samples obtained in Runs Nos. 713,719 and 720 showed traces offoaming and surface roughness.

EXAMPLE 21

Forty parts by weight of the uncured novolak resin used in Run No. 22(as a filler) was mixed in powder form with 60 parts by weight of eachof the product of Run No. 113, the product of Run No. 167, the productof Run No. 21, the powder of Run No. 22 and the powder of Run No. 23.Each of the mixtures was put in methanol heated in advance to 160° C.,extruded from a nozzle having a diameter of 1 mm under a pressure of 5kg/cm² and received in a square mold each side measuring 50 mm andhaving a depth of 25 mm. The resulting plate-like article was cooled toroom temperature and then withdrawn from the mold.

Table 32 summarizes the extrusion moldability of each of the mixtures,the apparent thickness and bulk density of each of the plate-likearticles extruded from the nozzle, and the shape of each plate-likearticle when it was heated to a temperature of 200° C. at a rate of 25°C./hour in a desiccator.

                                      TABLE 32                                    __________________________________________________________________________                           Plate-like article                                     Run            Extrusion                                                                             Apparent                                                                              Bulk   Shape upon heat-                        No.                                                                              Type of the filler                                                                        moldability                                                                           thickness (mm)                                                                        density (g/cc)                                                                       treatment at 200 ° C.            __________________________________________________________________________    721                                                                              Product of Run No. 113                                                                    Very good                                                                             24-25   0.3-0.4                                                                              Partly melted;                                                                shape retained.                         722                                                                              Product of Run No. 167                                                                    Very good                                                                             24-25   0.4-0.5                                                                              Infusible;                                                                    shape retained.                         723                                                                              Powder of Run No. 21                                                                      The nozzle was                                                                        12-13   0.7-0.8                                                                              Melted                                                 blocked up                                                                    gradually.                                                     724                                                                              Powder of Run No. 22                                                                      The nozzle was                                                                        19-20   0.6-0.7                                                                              Melted                                                 blocked up                                                                    gradually.                                                     725                                                                              Powder of Run No. 23                                                                      The nozzle was                                                                        2-3     0.9-1.0                                                                              Melted                                                 blocked up                                                                    within a short                                                                period of time.                                                __________________________________________________________________________

In the plate-like articles obtained in Runs Nos. 721 and 722, the fillerand the matrix were present in the uniformly mixed state. On the otherhand, in Runs Nos. 723 to 725, the proportion of the matrix increased asthe time passed after the extrusion of the articles from the nozzle.

What is claimed is:
 1. A resin composition comprising:(I) A granular or powdery resin which is a condensation product of a phenol and an aldehyde, and has a D₉₉₀ -1015/D1600 ratio of from 0.2 to 9.0 and D₈₉₀ /D₁₆₀₀ ratio of from 0.09 to 1.0 in its infrared absorption spectrum measured by a KBr tablet method, in which D₁₆₀₀ represents the absorption intensity of an absorption peak at 1600 cm⁻¹, D₉₉₀₋₁₀₁₅ represents the highest absorption intensity of absorption peaks in the range of 990 to 1015 cm⁻¹, and D₈₉₀ represents the absorption intensity of an absorption peak at 890 cm⁻¹, and is further characterized (A) in that at least 30% of the granular or powdery resin consists of spherical primary particles and their secondary agglomerated particles, each having a particle diameter of 0.1 to 150 microns, (B) by having such a size that at least 50% of weight thereof can pass through a 100 Tyler mesh sieve, and (C) by having a free phenol content, determined by liquid chromatography, of not more than 500 ppm, and (II) at least one curable resin selected from the group consisting of resol resins, novolak resins, epoxy resins, furan resins, melamine resins, urea resins and unsaturated polyester resins.
 2. The composition of claim 1 wherein the granular or powdery resin is the condensation product of the phenol, aldehyde and a nitrogen-containing compound having at least two active hydrogens.
 3. The composition of claim 1 wherein at least 70% by weight of the granular or powdery resin has a size that can pass through a 100 Tyler mesh sieve.
 4. The composition of claim 2 wherein the granular or powdery resin is a nitrogen-containing condensation.
 5. The composition of claim 4 wherein at least 70% by weight of the granular or powdery resin has a size that can pass through a 150 Tyler mesh sieve.
 6. The composition of claim 4 wherein the granular or powdery resin has a D₁₂₈₀₋₁₃₆₀ /D₁₄₅₀₋₁₅₀₀ ratio of from 0.15 to 3.0 in its infrared absorption spectrum measured by a KBr tablet method in which D₁₂₈₀₋₁₃₆₀ represents the highest absorption intensity of absorption peaks in the range of 1280 to 1360 cm⁻¹, and D₁₄₅₀₋₁₅₀₀ represents the highest absorption intensity of absorption peaks in the range of 1450 to 1500 cm⁻¹.
 7. The composition of claim 1 wherein the granular or powdery resin is at least partly fused when maintained at 100° C. for 5 minutes in accordance with the heat fusibility test described in the specification.
 8. The composition of claim 1 wherein the granular or powdery resin has a methanol solubility, S defined by the following equation, of at least 20% by weight ##EQU7## wherein W_(o) is the weight in grams of the resin, and W₁ is the weight in grams of the resin left after heating under reflux,and about 10 g of the resin is heated under reflux in 500 ml of substantially anhydrous material.
 9. The composition of claim 1 wherein the granular or powdery resin (I) does not substantially melt or melt-adhere when maintained at 100° C. for 5 minutes in accordance with the heat fusibility test described in the specification.
 10. The composition of claim 1 which further includes a filler material other than said granular or powdery resin (I).
 11. The composition of claim 10 wherein the proportion of the filler material is from about 10 to 77% by weight based on the total amount of the filler and granular or powdery resin (I).
 12. The composition of claim 1 which comprises from 20 to 80 parts by weight of the granular or powdery resin (I) and from 20 to 80 parts by weight of the curable resin (II).
 13. The composition of claim 10, which includes the filler material and wherein the filler material is an inorganic substance.
 14. The composition of claim 13 wherein the filler material is glass fibers, carbon fibers or rock wool.
 15. The composition of claim 13 wherein the filler material is carbon, silica, alumina, silica-alumina, diatomaceous earth, calcium carbonate, calcium silicate, magnesium oxide, clay, antimony oxide or hollow microspheres.
 16. The composition of claim 10, which includes the filler material and wherein the filler material is an organic material.
 17. The composition of claim 15 wherein the organic filler material is wood flour, linter, pulp or polyamide fibers.
 18. The composition of claims 1 wherein the proportion of said curable resin (3) is 10 to 90% by weight based on the total weight of it and the granular or powdery resin (I).
 19. The composition of claim 10 wherein the proportion of the filler material is 5 to 89% by weight based on the total weight of it and the granular or powdery resin (I). 